diff options
Diffstat (limited to 'drivers/gpio')
| -rw-r--r-- | drivers/gpio/gpio-elkhartlake.c | 14 | ||||
| -rw-r--r-- | drivers/gpio/gpio-ixp4xx.c | 51 | ||||
| -rw-r--r-- | drivers/gpio/gpio-max730x.c | 2 | ||||
| -rw-r--r-- | drivers/gpio/gpio-mmio.c | 49 | ||||
| -rw-r--r-- | drivers/gpio/gpio-mockup.c | 3 | ||||
| -rw-r--r-- | drivers/gpio/gpio-sifive.c | 1 | ||||
| -rw-r--r-- | drivers/gpio/gpio-sim.c | 24 | ||||
| -rw-r--r-- | drivers/gpio/gpio-stmpe.c | 6 | ||||
| -rw-r--r-- | drivers/gpio/gpio-tangier.c | 63 | ||||
| -rw-r--r-- | drivers/gpio/gpio-tangier.h | 4 | ||||
| -rw-r--r-- | drivers/gpio/gpio-wm831x.c | 14 | ||||
| -rw-r--r-- | drivers/gpio/gpio-wm8994.c | 13 | ||||
| -rw-r--r-- | drivers/gpio/gpio-xilinx.c | 1 | ||||
| -rw-r--r-- | drivers/gpio/gpiolib-cdev.c | 406 | ||||
| -rw-r--r-- | drivers/gpio/gpiolib-sysfs.c | 45 | ||||
| -rw-r--r-- | drivers/gpio/gpiolib-sysfs.h | 10 | ||||
| -rw-r--r-- | drivers/gpio/gpiolib.c | 201 | ||||
| -rw-r--r-- | drivers/gpio/gpiolib.h | 7 |
18 files changed, 532 insertions, 382 deletions
diff --git a/drivers/gpio/gpio-elkhartlake.c b/drivers/gpio/gpio-elkhartlake.c index a9c8b16215be..887c0fe99d39 100644 --- a/drivers/gpio/gpio-elkhartlake.c +++ b/drivers/gpio/gpio-elkhartlake.c @@ -55,18 +55,6 @@ static int ehl_gpio_probe(struct platform_device *pdev) return 0; } -static int ehl_gpio_suspend(struct device *dev) -{ - return tng_gpio_suspend(dev); -} - -static int ehl_gpio_resume(struct device *dev) -{ - return tng_gpio_resume(dev); -} - -static DEFINE_SIMPLE_DEV_PM_OPS(ehl_gpio_pm_ops, ehl_gpio_suspend, ehl_gpio_resume); - static const struct platform_device_id ehl_gpio_ids[] = { { "gpio-elkhartlake" }, { } @@ -76,7 +64,7 @@ MODULE_DEVICE_TABLE(platform, ehl_gpio_ids); static struct platform_driver ehl_gpio_driver = { .driver = { .name = "gpio-elkhartlake", - .pm = pm_sleep_ptr(&ehl_gpio_pm_ops), + .pm = pm_sleep_ptr(&tng_gpio_pm_ops), }, .probe = ehl_gpio_probe, .id_table = ehl_gpio_ids, diff --git a/drivers/gpio/gpio-ixp4xx.c b/drivers/gpio/gpio-ixp4xx.c index dde6cf3a5779..c5a9fa640566 100644 --- a/drivers/gpio/gpio-ixp4xx.c +++ b/drivers/gpio/gpio-ixp4xx.c @@ -38,6 +38,18 @@ #define IXP4XX_GPIO_STYLE_MASK GENMASK(2, 0) #define IXP4XX_GPIO_STYLE_SIZE 3 +/* + * Clock output control register defines. + */ +#define IXP4XX_GPCLK_CLK0DC_SHIFT 0 +#define IXP4XX_GPCLK_CLK0TC_SHIFT 4 +#define IXP4XX_GPCLK_CLK0_MASK GENMASK(7, 0) +#define IXP4XX_GPCLK_MUX14 BIT(8) +#define IXP4XX_GPCLK_CLK1DC_SHIFT 16 +#define IXP4XX_GPCLK_CLK1TC_SHIFT 20 +#define IXP4XX_GPCLK_CLK1_MASK GENMASK(23, 16) +#define IXP4XX_GPCLK_MUX15 BIT(24) + /** * struct ixp4xx_gpio - IXP4 GPIO state container * @dev: containing device for this instance @@ -202,6 +214,8 @@ static int ixp4xx_gpio_probe(struct platform_device *pdev) struct ixp4xx_gpio *g; struct gpio_irq_chip *girq; struct device_node *irq_parent; + bool clk_14, clk_15; + u32 val; int ret; g = devm_kzalloc(dev, sizeof(*g), GFP_KERNEL); @@ -226,12 +240,47 @@ static int ixp4xx_gpio_probe(struct platform_device *pdev) g->fwnode = of_node_to_fwnode(np); /* + * If either clock output is enabled explicitly in the device tree + * we take full control of the clock by masking off all bits for + * the clock control and selectively enabling them. Otherwise + * we leave the hardware default settings. + * + * Enable clock outputs with default timings of requested clock. + * If you need control over TC and DC, add these to the device + * tree bindings and use them here. + */ + clk_14 = of_property_read_bool(np, "intel,ixp4xx-gpio14-clkout"); + clk_15 = of_property_read_bool(np, "intel,ixp4xx-gpio15-clkout"); + + /* * Make sure GPIO 14 and 15 are NOT used as clocks but GPIO on * specific machines. */ if (of_machine_is_compatible("dlink,dsm-g600-a") || of_machine_is_compatible("iom,nas-100d")) - __raw_writel(0x0, g->base + IXP4XX_REG_GPCLK); + val = 0; + else { + val = __raw_readl(g->base + IXP4XX_REG_GPCLK); + + if (clk_14 || clk_15) { + val &= ~(IXP4XX_GPCLK_MUX14 | IXP4XX_GPCLK_MUX15); + val &= ~IXP4XX_GPCLK_CLK0_MASK; + val &= ~IXP4XX_GPCLK_CLK1_MASK; + if (clk_14) { + /* IXP4XX_GPCLK_CLK0DC implicit low */ + val |= (1 << IXP4XX_GPCLK_CLK0TC_SHIFT); + val |= IXP4XX_GPCLK_MUX14; + } + + if (clk_15) { + /* IXP4XX_GPCLK_CLK1DC implicit low */ + val |= (1 << IXP4XX_GPCLK_CLK1TC_SHIFT); + val |= IXP4XX_GPCLK_MUX15; + } + } + } + + __raw_writel(val, g->base + IXP4XX_REG_GPCLK); /* * This is a very special big-endian ARM issue: when the IXP4xx is diff --git a/drivers/gpio/gpio-max730x.c b/drivers/gpio/gpio-max730x.c index bb5cf14ae4c8..701795b9d329 100644 --- a/drivers/gpio/gpio-max730x.c +++ b/drivers/gpio/gpio-max730x.c @@ -1,5 +1,5 @@ // SPDX-License-Identifier: GPL-2.0-only -/** +/* * Copyright (C) 2006 Juergen Beisert, Pengutronix * Copyright (C) 2008 Guennadi Liakhovetski, Pengutronix * Copyright (C) 2009 Wolfram Sang, Pengutronix diff --git a/drivers/gpio/gpio-mmio.c b/drivers/gpio/gpio-mmio.c index 3ff0ea1e351c..71e1af7c2184 100644 --- a/drivers/gpio/gpio-mmio.c +++ b/drivers/gpio/gpio-mmio.c @@ -40,25 +40,22 @@ o ` ~~~~\___/~~~~ ` controller in FPGA is ,.` * `.......````.``` */ -#include <linux/init.h> +#include <linux/bitops.h> +#include <linux/compiler.h> #include <linux/err.h> -#include <linux/bug.h> -#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/io.h> +#include <linux/ioport.h> +#include <linux/log2.h> +#include <linux/mod_devicetable.h> #include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/property.h> +#include <linux/slab.h> #include <linux/spinlock.h> -#include <linux/compiler.h> #include <linux/types.h> -#include <linux/errno.h> -#include <linux/log2.h> -#include <linux/ioport.h> -#include <linux/io.h> + #include <linux/gpio/driver.h> -#include <linux/slab.h> -#include <linux/bitops.h> -#include <linux/platform_device.h> -#include <linux/property.h> -#include <linux/mod_devicetable.h> -#include <linux/of.h> #include "gpiolib.h" @@ -688,7 +685,6 @@ static void __iomem *bgpio_map(struct platform_device *pdev, return devm_ioremap_resource(&pdev->dev, r); } -#ifdef CONFIG_OF static const struct of_device_id bgpio_of_match[] = { { .compatible = "brcm,bcm6345-gpio" }, { .compatible = "wd,mbl-gpio" }, @@ -697,36 +693,27 @@ static const struct of_device_id bgpio_of_match[] = { }; MODULE_DEVICE_TABLE(of, bgpio_of_match); -static struct bgpio_pdata *bgpio_parse_dt(struct platform_device *pdev, - unsigned long *flags) +static struct bgpio_pdata *bgpio_parse_fw(struct device *dev, unsigned long *flags) { struct bgpio_pdata *pdata; - if (!pdev->dev.of_node) + if (!dev_fwnode(dev)) return NULL; - pdata = devm_kzalloc(&pdev->dev, sizeof(struct bgpio_pdata), - GFP_KERNEL); + pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL); if (!pdata) return ERR_PTR(-ENOMEM); pdata->base = -1; - if (of_device_is_big_endian(pdev->dev.of_node)) + if (device_is_big_endian(dev)) *flags |= BGPIOF_BIG_ENDIAN_BYTE_ORDER; - if (of_property_read_bool(pdev->dev.of_node, "no-output")) + if (device_property_read_bool(dev, "no-output")) *flags |= BGPIOF_NO_OUTPUT; return pdata; } -#else -static struct bgpio_pdata *bgpio_parse_dt(struct platform_device *pdev, - unsigned long *flags) -{ - return NULL; -} -#endif /* CONFIG_OF */ static int bgpio_pdev_probe(struct platform_device *pdev) { @@ -743,7 +730,7 @@ static int bgpio_pdev_probe(struct platform_device *pdev) struct gpio_chip *gc; struct bgpio_pdata *pdata; - pdata = bgpio_parse_dt(pdev, &flags); + pdata = bgpio_parse_fw(dev, &flags); if (IS_ERR(pdata)) return PTR_ERR(pdata); @@ -814,7 +801,7 @@ MODULE_DEVICE_TABLE(platform, bgpio_id_table); static struct platform_driver bgpio_driver = { .driver = { .name = "basic-mmio-gpio", - .of_match_table = of_match_ptr(bgpio_of_match), + .of_match_table = bgpio_of_match, }, .id_table = bgpio_id_table, .probe = bgpio_pdev_probe, diff --git a/drivers/gpio/gpio-mockup.c b/drivers/gpio/gpio-mockup.c index 4870e267a402..455eecf6380e 100644 --- a/drivers/gpio/gpio-mockup.c +++ b/drivers/gpio/gpio-mockup.c @@ -354,7 +354,6 @@ static const struct file_operations gpio_mockup_debugfs_ops = { static void gpio_mockup_debugfs_setup(struct device *dev, struct gpio_mockup_chip *chip) { - struct device *child __free(put_device) = NULL; struct gpio_mockup_dbgfs_private *priv; struct gpio_chip *gc; const char *devname; @@ -367,7 +366,7 @@ static void gpio_mockup_debugfs_setup(struct device *dev, * There can only be a single GPIO device per platform device in * gpio-mockup so using device_find_any_child() is OK. */ - child = device_find_any_child(dev); + struct device *child __free(put_device) = device_find_any_child(dev); if (!child) return; diff --git a/drivers/gpio/gpio-sifive.c b/drivers/gpio/gpio-sifive.c index 8decd9b5d229..067c8edb62e2 100644 --- a/drivers/gpio/gpio-sifive.c +++ b/drivers/gpio/gpio-sifive.c @@ -250,7 +250,6 @@ static int sifive_gpio_probe(struct platform_device *pdev) girq->handler = handle_bad_irq; girq->default_type = IRQ_TYPE_NONE; - platform_set_drvdata(pdev, chip); return gpiochip_add_data(&chip->gc, chip); } diff --git a/drivers/gpio/gpio-sim.c b/drivers/gpio/gpio-sim.c index 1928209491e1..c4106e37e6db 100644 --- a/drivers/gpio/gpio-sim.c +++ b/drivers/gpio/gpio-sim.c @@ -20,6 +20,7 @@ #include <linux/interrupt.h> #include <linux/irq.h> #include <linux/irq_sim.h> +#include <linux/kernel.h> #include <linux/list.h> #include <linux/minmax.h> #include <linux/mod_devicetable.h> @@ -28,6 +29,7 @@ #include <linux/notifier.h> #include <linux/platform_device.h> #include <linux/property.h> +#include <linux/seq_file.h> #include <linux/slab.h> #include <linux/string.h> #include <linux/string_helpers.h> @@ -224,6 +226,25 @@ static void gpio_sim_free(struct gpio_chip *gc, unsigned int offset) } } +static void gpio_sim_dbg_show(struct seq_file *seq, struct gpio_chip *gc) +{ + struct gpio_sim_chip *chip = gpiochip_get_data(gc); + const char *label; + int i; + + guard(mutex)(&chip->lock); + + for_each_requested_gpio(gc, i, label) + seq_printf(seq, " gpio-%-3d (%s) %s,%s\n", + gc->base + i, + label, + test_bit(i, chip->direction_map) ? "input" : + test_bit(i, chip->value_map) ? "output-high" : + "output-low", + test_bit(i, chip->pull_map) ? "pull-up" : + "pull-down"); +} + static ssize_t gpio_sim_sysfs_val_show(struct device *dev, struct device_attribute *attr, char *buf) { @@ -460,6 +481,7 @@ static int gpio_sim_add_bank(struct fwnode_handle *swnode, struct device *dev) gc->to_irq = gpio_sim_to_irq; gc->request = gpio_sim_request; gc->free = gpio_sim_free; + gc->dbg_show = PTR_IF(IS_ENABLED(CONFIG_DEBUG_FS), gpio_sim_dbg_show); gc->can_sleep = true; ret = devm_gpiochip_add_data(dev, gc, chip); @@ -1546,6 +1568,6 @@ static void __exit gpio_sim_exit(void) } module_exit(gpio_sim_exit); -MODULE_AUTHOR("Bartosz Golaszewski <brgl@bgdev.pl"); +MODULE_AUTHOR("Bartosz Golaszewski <brgl@bgdev.pl>"); MODULE_DESCRIPTION("GPIO Simulator Module"); MODULE_LICENSE("GPL"); diff --git a/drivers/gpio/gpio-stmpe.c b/drivers/gpio/gpio-stmpe.c index 27cc4da53565..6c5ee81d71b3 100644 --- a/drivers/gpio/gpio-stmpe.c +++ b/drivers/gpio/gpio-stmpe.c @@ -5,6 +5,7 @@ * Author: Rabin Vincent <rabin.vincent@stericsson.com> for ST-Ericsson */ +#include <linux/cleanup.h> #include <linux/init.h> #include <linux/platform_device.h> #include <linux/slab.h> @@ -255,7 +256,6 @@ static void stmpe_dbg_show_one(struct seq_file *s, { struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(gc); struct stmpe *stmpe = stmpe_gpio->stmpe; - const char *label = gpiochip_is_requested(gc, offset); bool val = !!stmpe_gpio_get(gc, offset); u8 bank = offset / 8; u8 dir_reg = stmpe->regs[STMPE_IDX_GPDR_LSB + bank]; @@ -263,6 +263,10 @@ static void stmpe_dbg_show_one(struct seq_file *s, int ret; u8 dir; + char *label __free(kfree) = gpiochip_dup_line_label(gc, offset); + if (IS_ERR(label)) + return; + ret = stmpe_reg_read(stmpe, dir_reg); if (ret < 0) return; diff --git a/drivers/gpio/gpio-tangier.c b/drivers/gpio/gpio-tangier.c index 7ce3eddaed25..b75e0b12087a 100644 --- a/drivers/gpio/gpio-tangier.c +++ b/drivers/gpio/gpio-tangier.c @@ -10,6 +10,7 @@ */ #include <linux/bitops.h> +#include <linux/cleanup.h> #include <linux/device.h> #include <linux/errno.h> #include <linux/export.h> @@ -19,6 +20,7 @@ #include <linux/math.h> #include <linux/module.h> #include <linux/pinctrl/pinconf-generic.h> +#include <linux/pm.h> #include <linux/spinlock.h> #include <linux/string_helpers.h> #include <linux/types.h> @@ -91,37 +93,31 @@ static int tng_gpio_get(struct gpio_chip *chip, unsigned int offset) static void tng_gpio_set(struct gpio_chip *chip, unsigned int offset, int value) { struct tng_gpio *priv = gpiochip_get_data(chip); - unsigned long flags; void __iomem *reg; u8 shift; reg = gpio_reg_and_bit(chip, offset, value ? GPSR : GPCR, &shift); - raw_spin_lock_irqsave(&priv->lock, flags); + guard(raw_spinlock_irqsave)(&priv->lock); writel(BIT(shift), reg); - - raw_spin_unlock_irqrestore(&priv->lock, flags); } static int tng_gpio_direction_input(struct gpio_chip *chip, unsigned int offset) { struct tng_gpio *priv = gpiochip_get_data(chip); - unsigned long flags; void __iomem *gpdr; u32 value; u8 shift; gpdr = gpio_reg_and_bit(chip, offset, GPDR, &shift); - raw_spin_lock_irqsave(&priv->lock, flags); + guard(raw_spinlock_irqsave)(&priv->lock); value = readl(gpdr); value &= ~BIT(shift); writel(value, gpdr); - raw_spin_unlock_irqrestore(&priv->lock, flags); - return 0; } @@ -129,21 +125,18 @@ static int tng_gpio_direction_output(struct gpio_chip *chip, unsigned int offset int value) { struct tng_gpio *priv = gpiochip_get_data(chip); - unsigned long flags; void __iomem *gpdr; u8 shift; gpdr = gpio_reg_and_bit(chip, offset, GPDR, &shift); tng_gpio_set(chip, offset, value); - raw_spin_lock_irqsave(&priv->lock, flags); + guard(raw_spinlock_irqsave)(&priv->lock); value = readl(gpdr); value |= BIT(shift); writel(value, gpdr); - raw_spin_unlock_irqrestore(&priv->lock, flags); - return 0; } @@ -164,14 +157,13 @@ static int tng_gpio_set_debounce(struct gpio_chip *chip, unsigned int offset, unsigned int debounce) { struct tng_gpio *priv = gpiochip_get_data(chip); - unsigned long flags; void __iomem *gfbr; u32 value; u8 shift; gfbr = gpio_reg_and_bit(chip, offset, GFBR, &shift); - raw_spin_lock_irqsave(&priv->lock, flags); + guard(raw_spinlock_irqsave)(&priv->lock); value = readl(gfbr); if (debounce) @@ -180,8 +172,6 @@ static int tng_gpio_set_debounce(struct gpio_chip *chip, unsigned int offset, value |= BIT(shift); writel(value, gfbr); - raw_spin_unlock_irqrestore(&priv->lock, flags); - return 0; } @@ -207,27 +197,25 @@ static void tng_irq_ack(struct irq_data *d) { struct tng_gpio *priv = irq_data_get_irq_chip_data(d); irq_hw_number_t gpio = irqd_to_hwirq(d); - unsigned long flags; void __iomem *gisr; u8 shift; gisr = gpio_reg_and_bit(&priv->chip, gpio, GISR, &shift); - raw_spin_lock_irqsave(&priv->lock, flags); + guard(raw_spinlock_irqsave)(&priv->lock); + writel(BIT(shift), gisr); - raw_spin_unlock_irqrestore(&priv->lock, flags); } static void tng_irq_unmask_mask(struct tng_gpio *priv, u32 gpio, bool unmask) { - unsigned long flags; void __iomem *gimr; u32 value; u8 shift; gimr = gpio_reg_and_bit(&priv->chip, gpio, GIMR, &shift); - raw_spin_lock_irqsave(&priv->lock, flags); + guard(raw_spinlock_irqsave)(&priv->lock); value = readl(gimr); if (unmask) @@ -235,8 +223,6 @@ static void tng_irq_unmask_mask(struct tng_gpio *priv, u32 gpio, bool unmask) else value &= ~BIT(shift); writel(value, gimr); - - raw_spin_unlock_irqrestore(&priv->lock, flags); } static void tng_irq_mask(struct irq_data *d) @@ -267,10 +253,9 @@ static int tng_irq_set_type(struct irq_data *d, unsigned int type) void __iomem *gitr = gpio_reg(&priv->chip, gpio, GITR); void __iomem *glpr = gpio_reg(&priv->chip, gpio, GLPR); u8 shift = gpio % 32; - unsigned long flags; u32 value; - raw_spin_lock_irqsave(&priv->lock, flags); + guard(raw_spinlock_irqsave)(&priv->lock); value = readl(grer); if (type & IRQ_TYPE_EDGE_RISING) @@ -311,8 +296,6 @@ static int tng_irq_set_type(struct irq_data *d, unsigned int type) irq_set_handler_locked(d, handle_edge_irq); } - raw_spin_unlock_irqrestore(&priv->lock, flags); - return 0; } @@ -324,10 +307,11 @@ static int tng_irq_set_wake(struct irq_data *d, unsigned int on) void __iomem *gwmr = gpio_reg(&priv->chip, gpio, priv->wake_regs.gwmr); void __iomem *gwsr = gpio_reg(&priv->chip, gpio, priv->wake_regs.gwsr); u8 shift = gpio % 32; - unsigned long flags; u32 value; - raw_spin_lock_irqsave(&priv->lock, flags); + dev_dbg(priv->dev, "%s wake for gpio %lu\n", str_enable_disable(on), gpio); + + guard(raw_spinlock_irqsave)(&priv->lock); /* Clear the existing wake status */ writel(BIT(shift), gwsr); @@ -339,9 +323,6 @@ static int tng_irq_set_wake(struct irq_data *d, unsigned int on) value &= ~BIT(shift); writel(value, gwmr); - raw_spin_unlock_irqrestore(&priv->lock, flags); - - dev_dbg(priv->dev, "%s wake for gpio %lu\n", str_enable_disable(on), gpio); return 0; } @@ -477,14 +458,13 @@ int devm_tng_gpio_probe(struct device *dev, struct tng_gpio *gpio) } EXPORT_SYMBOL_NS_GPL(devm_tng_gpio_probe, GPIO_TANGIER); -int tng_gpio_suspend(struct device *dev) +static int tng_gpio_suspend(struct device *dev) { struct tng_gpio *priv = dev_get_drvdata(dev); struct tng_gpio_context *ctx = priv->ctx; - unsigned long flags; unsigned int base; - raw_spin_lock_irqsave(&priv->lock, flags); + guard(raw_spinlock_irqsave)(&priv->lock); for (base = 0; base < priv->chip.ngpio; base += 32, ctx++) { /* GPLR is RO, values read will be restored using GPSR */ @@ -498,20 +478,16 @@ int tng_gpio_suspend(struct device *dev) ctx->gwmr = readl(gpio_reg(&priv->chip, base, priv->wake_regs.gwmr)); } - raw_spin_unlock_irqrestore(&priv->lock, flags); - return 0; } -EXPORT_SYMBOL_NS_GPL(tng_gpio_suspend, GPIO_TANGIER); -int tng_gpio_resume(struct device *dev) +static int tng_gpio_resume(struct device *dev) { struct tng_gpio *priv = dev_get_drvdata(dev); struct tng_gpio_context *ctx = priv->ctx; - unsigned long flags; unsigned int base; - raw_spin_lock_irqsave(&priv->lock, flags); + guard(raw_spinlock_irqsave)(&priv->lock); for (base = 0; base < priv->chip.ngpio; base += 32, ctx++) { /* GPLR is RO, values read will be restored using GPSR */ @@ -525,11 +501,10 @@ int tng_gpio_resume(struct device *dev) writel(ctx->gwmr, gpio_reg(&priv->chip, base, priv->wake_regs.gwmr)); } - raw_spin_unlock_irqrestore(&priv->lock, flags); - return 0; } -EXPORT_SYMBOL_NS_GPL(tng_gpio_resume, GPIO_TANGIER); + +EXPORT_NS_GPL_SIMPLE_DEV_PM_OPS(tng_gpio_pm_ops, tng_gpio_suspend, tng_gpio_resume, GPIO_TANGIER); MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>"); MODULE_AUTHOR("Pandith N <pandith.n@intel.com>"); diff --git a/drivers/gpio/gpio-tangier.h b/drivers/gpio/gpio-tangier.h index 16c4f22908fb..ca7ab6cf6fa5 100644 --- a/drivers/gpio/gpio-tangier.h +++ b/drivers/gpio/gpio-tangier.h @@ -13,6 +13,7 @@ #define _GPIO_TANGIER_H_ #include <linux/gpio/driver.h> +#include <linux/pm.h> #include <linux/spinlock_types.h> #include <linux/types.h> @@ -111,7 +112,6 @@ struct tng_gpio { int devm_tng_gpio_probe(struct device *dev, struct tng_gpio *gpio); -int tng_gpio_suspend(struct device *dev); -int tng_gpio_resume(struct device *dev); +extern const struct dev_pm_ops tng_gpio_pm_ops; #endif /* _GPIO_TANGIER_H_ */ diff --git a/drivers/gpio/gpio-wm831x.c b/drivers/gpio/gpio-wm831x.c index 7eaf8a28638c..f7d5120ff8f1 100644 --- a/drivers/gpio/gpio-wm831x.c +++ b/drivers/gpio/gpio-wm831x.c @@ -8,6 +8,7 @@ * */ +#include <linux/cleanup.h> #include <linux/kernel.h> #include <linux/slab.h> #include <linux/module.h> @@ -160,18 +161,21 @@ static void wm831x_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip) for (i = 0; i < chip->ngpio; i++) { int gpio = i + chip->base; int reg; - const char *label, *pull, *powerdomain; + const char *pull, *powerdomain; /* We report the GPIO even if it's not requested since * we're also reporting things like alternate * functions which apply even when the GPIO is not in * use as a GPIO. */ - label = gpiochip_is_requested(chip, i); - if (!label) - label = "Unrequested"; + char *label __free(kfree) = gpiochip_dup_line_label(chip, i); + if (IS_ERR(label)) { + dev_err(wm831x->dev, "Failed to duplicate label\n"); + continue; + } - seq_printf(s, " gpio-%-3d (%-20.20s) ", gpio, label); + seq_printf(s, " gpio-%-3d (%-20.20s) ", + gpio, label ?: "Unrequested"); reg = wm831x_reg_read(wm831x, WM831X_GPIO1_CONTROL + i); if (reg < 0) { diff --git a/drivers/gpio/gpio-wm8994.c b/drivers/gpio/gpio-wm8994.c index f4a474cef32d..bf05c9b5882b 100644 --- a/drivers/gpio/gpio-wm8994.c +++ b/drivers/gpio/gpio-wm8994.c @@ -8,6 +8,7 @@ * */ +#include <linux/cleanup.h> #include <linux/kernel.h> #include <linux/slab.h> #include <linux/module.h> @@ -193,18 +194,20 @@ static void wm8994_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip) for (i = 0; i < chip->ngpio; i++) { int gpio = i + chip->base; int reg; - const char *label; /* We report the GPIO even if it's not requested since * we're also reporting things like alternate * functions which apply even when the GPIO is not in * use as a GPIO. */ - label = gpiochip_is_requested(chip, i); - if (!label) - label = "Unrequested"; + char *label __free(kfree) = gpiochip_dup_line_label(chip, i); + if (IS_ERR(label)) { + dev_err(wm8994->dev, "Failed to duplicate label\n"); + continue; + } - seq_printf(s, " gpio-%-3d (%-20.20s) ", gpio, label); + seq_printf(s, " gpio-%-3d (%-20.20s) ", gpio, + label ?: "Unrequested"); reg = wm8994_reg_read(wm8994, WM8994_GPIO_1 + i); if (reg < 0) { diff --git a/drivers/gpio/gpio-xilinx.c b/drivers/gpio/gpio-xilinx.c index 823198368250..7348df385198 100644 --- a/drivers/gpio/gpio-xilinx.c +++ b/drivers/gpio/gpio-xilinx.c @@ -52,7 +52,6 @@ * @dir: GPIO direction shadow register * @gpio_lock: Lock used for synchronization * @irq: IRQ used by GPIO device - * @irqchip: IRQ chip * @enable: GPIO IRQ enable/disable bitfield * @rising_edge: GPIO IRQ rising edge enable/disable bitfield * @falling_edge: GPIO IRQ falling edge enable/disable bitfield diff --git a/drivers/gpio/gpiolib-cdev.c b/drivers/gpio/gpiolib-cdev.c index f713d1ef7746..9155c54acc1e 100644 --- a/drivers/gpio/gpiolib-cdev.c +++ b/drivers/gpio/gpiolib-cdev.c @@ -5,6 +5,7 @@ #include <linux/bitmap.h> #include <linux/build_bug.h> #include <linux/cdev.h> +#include <linux/cleanup.h> #include <linux/compat.h> #include <linux/compiler.h> #include <linux/device.h> @@ -21,6 +22,7 @@ #include <linux/mutex.h> #include <linux/pinctrl/consumer.h> #include <linux/poll.h> +#include <linux/rbtree.h> #include <linux/seq_file.h> #include <linux/spinlock.h> #include <linux/timekeeping.h> @@ -461,6 +463,7 @@ out_free_lh: /** * struct line - contains the state of a requested line + * @node: to store the object in supinfo_tree if supplemental * @desc: the GPIO descriptor for this line. * @req: the corresponding line request * @irq: the interrupt triggered in response to events on this GPIO @@ -473,6 +476,7 @@ out_free_lh: * @line_seqno: the seqno for the current edge event in the sequence of * events for this line. * @work: the worker that implements software debouncing + * @debounce_period_us: the debounce period in microseconds * @sw_debounced: flag indicating if the software debouncer is active * @level: the current debounced physical level of the line * @hdesc: the Hardware Timestamp Engine (HTE) descriptor @@ -481,6 +485,7 @@ out_free_lh: * @last_seqno: the last sequence number before debounce period expires */ struct line { + struct rb_node node; struct gpio_desc *desc; /* * -- edge detector specific fields -- @@ -515,6 +520,15 @@ struct line { */ struct delayed_work work; /* + * debounce_period_us is accessed by debounce_irq_handler() and + * process_hw_ts() which are disabled when modified by + * debounce_setup(), edge_detector_setup() or edge_detector_stop() + * or can live with a stale version when updated by + * edge_detector_update(). + * The modifying functions are themselves mutually exclusive. + */ + unsigned int debounce_period_us; + /* * sw_debounce is accessed by linereq_set_config(), which is the * only setter, and linereq_get_values(), which can live with a * slightly stale value. @@ -546,6 +560,17 @@ struct line { #endif /* CONFIG_HTE */ }; +/* + * a rbtree of the struct lines containing supplemental info. + * Used to populate gpio_v2_line_info with cdev specific fields not contained + * in the struct gpio_desc. + * A line is determined to contain supplemental information by + * line_has_supinfo(). + */ +static struct rb_root supinfo_tree = RB_ROOT; +/* covers supinfo_tree */ +static DEFINE_SPINLOCK(supinfo_lock); + /** * struct linereq - contains the state of a userspace line request * @gdev: the GPIO device the line request pertains to @@ -559,7 +584,8 @@ struct line { * this line request. Note that this is not used when @num_lines is 1, as * the line_seqno is then the same and is cheaper to calculate. * @config_mutex: mutex for serializing ioctl() calls to ensure consistency - * of configuration, particularly multi-step accesses to desc flags. + * of configuration, particularly multi-step accesses to desc flags and + * changes to supinfo status. * @lines: the lines held by this line request, with @num_lines elements. */ struct linereq { @@ -575,6 +601,103 @@ struct linereq { struct line lines[] __counted_by(num_lines); }; +static void supinfo_insert(struct line *line) +{ + struct rb_node **new = &(supinfo_tree.rb_node), *parent = NULL; + struct line *entry; + + guard(spinlock)(&supinfo_lock); + + while (*new) { + entry = container_of(*new, struct line, node); + + parent = *new; + if (line->desc < entry->desc) { + new = &((*new)->rb_left); + } else if (line->desc > entry->desc) { + new = &((*new)->rb_right); + } else { + /* this should never happen */ + WARN(1, "duplicate line inserted"); + return; + } + } + + rb_link_node(&line->node, parent, new); + rb_insert_color(&line->node, &supinfo_tree); +} + +static void supinfo_erase(struct line *line) +{ + guard(spinlock)(&supinfo_lock); + + rb_erase(&line->node, &supinfo_tree); +} + +static struct line *supinfo_find(struct gpio_desc *desc) +{ + struct rb_node *node = supinfo_tree.rb_node; + struct line *line; + + while (node) { + line = container_of(node, struct line, node); + if (desc < line->desc) + node = node->rb_left; + else if (desc > line->desc) + node = node->rb_right; + else + return line; + } + return NULL; +} + +static void supinfo_to_lineinfo(struct gpio_desc *desc, + struct gpio_v2_line_info *info) +{ + struct gpio_v2_line_attribute *attr; + struct line *line; + + guard(spinlock)(&supinfo_lock); + + line = supinfo_find(desc); + if (!line) + return; + + attr = &info->attrs[info->num_attrs]; + attr->id = GPIO_V2_LINE_ATTR_ID_DEBOUNCE; + attr->debounce_period_us = READ_ONCE(line->debounce_period_us); + info->num_attrs++; +} + +static inline bool line_has_supinfo(struct line *line) +{ + return READ_ONCE(line->debounce_period_us); +} + +/* + * Checks line_has_supinfo() before and after the change to avoid unnecessary + * supinfo_tree access. + * Called indirectly by linereq_create() or linereq_set_config() so line + * is already protected from concurrent changes. + */ +static void line_set_debounce_period(struct line *line, + unsigned int debounce_period_us) +{ + bool was_suppl = line_has_supinfo(line); + + WRITE_ONCE(line->debounce_period_us, debounce_period_us); + + /* if supinfo status is unchanged then we're done */ + if (line_has_supinfo(line) == was_suppl) + return; + + /* supinfo status has changed, so update the tree */ + if (was_suppl) + supinfo_erase(line); + else + supinfo_insert(line); +} + #define GPIO_V2_LINE_BIAS_FLAGS \ (GPIO_V2_LINE_FLAG_BIAS_PULL_UP | \ GPIO_V2_LINE_FLAG_BIAS_PULL_DOWN | \ @@ -625,13 +748,13 @@ static void linereq_put_event(struct linereq *lr, { bool overflow = false; - spin_lock(&lr->wait.lock); - if (kfifo_is_full(&lr->events)) { - overflow = true; - kfifo_skip(&lr->events); + scoped_guard(spinlock, &lr->wait.lock) { + if (kfifo_is_full(&lr->events)) { + overflow = true; + kfifo_skip(&lr->events); + } + kfifo_in(&lr->events, le, 1); } - kfifo_in(&lr->events, le, 1); - spin_unlock(&lr->wait.lock); if (!overflow) wake_up_poll(&lr->wait, EPOLLIN); else @@ -723,7 +846,7 @@ static enum hte_return process_hw_ts(struct hte_ts_data *ts, void *p) line->total_discard_seq++; line->last_seqno = ts->seq; mod_delayed_work(system_wq, &line->work, - usecs_to_jiffies(READ_ONCE(line->desc->debounce_period_us))); + usecs_to_jiffies(READ_ONCE(line->debounce_period_us))); } else { if (unlikely(ts->seq < line->line_seqno)) return HTE_CB_HANDLED; @@ -864,7 +987,7 @@ static irqreturn_t debounce_irq_handler(int irq, void *p) struct line *line = p; mod_delayed_work(system_wq, &line->work, - usecs_to_jiffies(READ_ONCE(line->desc->debounce_period_us))); + usecs_to_jiffies(READ_ONCE(line->debounce_period_us))); return IRQ_HANDLED; } @@ -946,7 +1069,7 @@ static int debounce_setup(struct line *line, unsigned int debounce_period_us) /* try hardware */ ret = gpiod_set_debounce(line->desc, debounce_period_us); if (!ret) { - WRITE_ONCE(line->desc->debounce_period_us, debounce_period_us); + line_set_debounce_period(line, debounce_period_us); return ret; } if (ret != -ENOTSUPP) @@ -1025,8 +1148,7 @@ static void edge_detector_stop(struct line *line) cancel_delayed_work_sync(&line->work); WRITE_ONCE(line->sw_debounced, 0); WRITE_ONCE(line->edflags, 0); - if (line->desc) - WRITE_ONCE(line->desc->debounce_period_us, 0); + line_set_debounce_period(line, 0); /* do not change line->level - see comment in debounced_value() */ } @@ -1051,7 +1173,7 @@ static int edge_detector_setup(struct line *line, ret = debounce_setup(line, debounce_period_us); if (ret) return ret; - WRITE_ONCE(line->desc->debounce_period_us, debounce_period_us); + line_set_debounce_period(line, debounce_period_us); } /* detection disabled or sw debouncer will provide edge detection */ @@ -1093,12 +1215,12 @@ static int edge_detector_update(struct line *line, gpio_v2_line_config_debounce_period(lc, line_idx); if ((active_edflags == edflags) && - (READ_ONCE(line->desc->debounce_period_us) == debounce_period_us)) + (READ_ONCE(line->debounce_period_us) == debounce_period_us)) return 0; /* sw debounced and still will be...*/ if (debounce_period_us && READ_ONCE(line->sw_debounced)) { - WRITE_ONCE(line->desc->debounce_period_us, debounce_period_us); + line_set_debounce_period(line, debounce_period_us); return 0; } @@ -1272,9 +1394,18 @@ static long linereq_get_values(struct linereq *lr, void __user *ip) if (copy_from_user(&lv, ip, sizeof(lv))) return -EFAULT; + /* + * gpiod_get_array_value_complex() requires compacted desc and val + * arrays, rather than the sparse ones in lv. + * Calculation of num_get and construction of the desc array is + * optimized to avoid allocation for the desc array for the common + * num_get == 1 case. + */ + /* scan requested lines to calculate the subset to get */ for (num_get = 0, i = 0; i < lr->num_lines; i++) { if (lv.mask & BIT_ULL(i)) { num_get++; + /* capture desc for the num_get == 1 case */ descs = &lr->lines[i].desc; } } @@ -1283,6 +1414,7 @@ static long linereq_get_values(struct linereq *lr, void __user *ip) return -EINVAL; if (num_get != 1) { + /* build compacted desc array */ descs = kmalloc_array(num_get, sizeof(*descs), GFP_KERNEL); if (!descs) return -ENOMEM; @@ -1303,6 +1435,7 @@ static long linereq_get_values(struct linereq *lr, void __user *ip) lv.bits = 0; for (didx = 0, i = 0; i < lr->num_lines; i++) { + /* unpack compacted vals for the response */ if (lv.mask & BIT_ULL(i)) { if (lr->lines[i].sw_debounced) val = debounced_value(&lr->lines[i]); @@ -1328,14 +1461,25 @@ static long linereq_set_values_unlocked(struct linereq *lr, unsigned int i, didx, num_set; int ret; + /* + * gpiod_set_array_value_complex() requires compacted desc and val + * arrays, rather than the sparse ones in lv. + * Calculation of num_set and construction of the descs and vals arrays + * is optimized to minimize scanning the lv->mask, and to avoid + * allocation for the desc array for the common num_set == 1 case. + */ bitmap_zero(vals, GPIO_V2_LINES_MAX); + /* scan requested lines to determine the subset to be set */ for (num_set = 0, i = 0; i < lr->num_lines; i++) { if (lv->mask & BIT_ULL(i)) { + /* setting inputs is not allowed */ if (!test_bit(FLAG_IS_OUT, &lr->lines[i].desc->flags)) return -EPERM; + /* add to compacted values */ if (lv->bits & BIT_ULL(i)) __set_bit(num_set, vals); num_set++; + /* capture desc for the num_set == 1 case */ descs = &lr->lines[i].desc; } } @@ -1343,7 +1487,7 @@ static long linereq_set_values_unlocked(struct linereq *lr, return -EINVAL; if (num_set != 1) { - /* build compacted desc array and values */ + /* build compacted desc array */ descs = kmalloc_array(num_set, sizeof(*descs), GFP_KERNEL); if (!descs) return -ENOMEM; @@ -1365,18 +1509,13 @@ static long linereq_set_values_unlocked(struct linereq *lr, static long linereq_set_values(struct linereq *lr, void __user *ip) { struct gpio_v2_line_values lv; - int ret; if (copy_from_user(&lv, ip, sizeof(lv))) return -EFAULT; - mutex_lock(&lr->config_mutex); - - ret = linereq_set_values_unlocked(lr, &lv); + guard(mutex)(&lr->config_mutex); - mutex_unlock(&lr->config_mutex); - - return ret; + return linereq_set_values_unlocked(lr, &lv); } static long linereq_set_config_unlocked(struct linereq *lr, @@ -1434,13 +1573,9 @@ static long linereq_set_config(struct linereq *lr, void __user *ip) if (ret) return ret; - mutex_lock(&lr->config_mutex); - - ret = linereq_set_config_unlocked(lr, &lc); + guard(mutex)(&lr->config_mutex); - mutex_unlock(&lr->config_mutex); - - return ret; + return linereq_set_config_unlocked(lr, &lc); } static long linereq_ioctl_unlocked(struct file *file, unsigned int cmd, @@ -1522,28 +1657,22 @@ static ssize_t linereq_read_unlocked(struct file *file, char __user *buf, return -EINVAL; do { - spin_lock(&lr->wait.lock); - if (kfifo_is_empty(&lr->events)) { - if (bytes_read) { - spin_unlock(&lr->wait.lock); - return bytes_read; - } - - if (file->f_flags & O_NONBLOCK) { - spin_unlock(&lr->wait.lock); - return -EAGAIN; + scoped_guard(spinlock, &lr->wait.lock) { + if (kfifo_is_empty(&lr->events)) { + if (bytes_read) + return bytes_read; + + if (file->f_flags & O_NONBLOCK) + return -EAGAIN; + + ret = wait_event_interruptible_locked(lr->wait, + !kfifo_is_empty(&lr->events)); + if (ret) + return ret; } - ret = wait_event_interruptible_locked(lr->wait, - !kfifo_is_empty(&lr->events)); - if (ret) { - spin_unlock(&lr->wait.lock); - return ret; - } + ret = kfifo_out(&lr->events, &le, 1); } - - ret = kfifo_out(&lr->events, &le, 1); - spin_unlock(&lr->wait.lock); if (ret != 1) { /* * This should never happen - we were holding the @@ -1573,6 +1702,7 @@ static ssize_t linereq_read(struct file *file, char __user *buf, static void linereq_free(struct linereq *lr) { + struct line *line; unsigned int i; if (lr->device_unregistered_nb.notifier_call) @@ -1580,10 +1710,14 @@ static void linereq_free(struct linereq *lr) &lr->device_unregistered_nb); for (i = 0; i < lr->num_lines; i++) { - if (lr->lines[i].desc) { - edge_detector_stop(&lr->lines[i]); - gpiod_free(lr->lines[i].desc); - } + line = &lr->lines[i]; + if (!line->desc) + continue; + + edge_detector_stop(line); + if (line_has_supinfo(line)) + supinfo_erase(line); + gpiod_free(line->desc); } kfifo_free(&lr->events); kfree(lr->label); @@ -1888,28 +2022,22 @@ static ssize_t lineevent_read_unlocked(struct file *file, char __user *buf, return -EINVAL; do { - spin_lock(&le->wait.lock); - if (kfifo_is_empty(&le->events)) { - if (bytes_read) { - spin_unlock(&le->wait.lock); - return bytes_read; + scoped_guard(spinlock, &le->wait.lock) { + if (kfifo_is_empty(&le->events)) { + if (bytes_read) + return bytes_read; + + if (file->f_flags & O_NONBLOCK) + return -EAGAIN; + + ret = wait_event_interruptible_locked(le->wait, + !kfifo_is_empty(&le->events)); + if (ret) + return ret; } - if (file->f_flags & O_NONBLOCK) { - spin_unlock(&le->wait.lock); - return -EAGAIN; - } - - ret = wait_event_interruptible_locked(le->wait, - !kfifo_is_empty(&le->events)); - if (ret) { - spin_unlock(&le->wait.lock); - return ret; - } + ret = kfifo_out(&le->events, &ge, 1); } - - ret = kfifo_out(&le->events, &ge, 1); - spin_unlock(&le->wait.lock); if (ret != 1) { /* * This should never happen - we were holding the lock @@ -2272,84 +2400,72 @@ static void gpio_desc_to_lineinfo(struct gpio_desc *desc, struct gpio_v2_line_info *info) { struct gpio_chip *gc = desc->gdev->chip; - bool ok_for_pinctrl; - unsigned long flags; - u32 debounce_period_us; - unsigned int num_attrs = 0; + unsigned long dflags; memset(info, 0, sizeof(*info)); info->offset = gpio_chip_hwgpio(desc); - /* - * This function takes a mutex so we must check this before taking - * the spinlock. - * - * FIXME: find a non-racy way to retrieve this information. Maybe a - * lock common to both frameworks? - */ - ok_for_pinctrl = pinctrl_gpio_can_use_line(gc, info->offset); - - spin_lock_irqsave(&gpio_lock, flags); + scoped_guard(spinlock_irqsave, &gpio_lock) { + if (desc->name) + strscpy(info->name, desc->name, sizeof(info->name)); - if (desc->name) - strscpy(info->name, desc->name, sizeof(info->name)); + if (desc->label) + strscpy(info->consumer, desc->label, + sizeof(info->consumer)); - if (desc->label) - strscpy(info->consumer, desc->label, sizeof(info->consumer)); + dflags = READ_ONCE(desc->flags); + } /* - * Userspace only need to know that the kernel is using this GPIO so - * it can't use it. + * Userspace only need know that the kernel is using this GPIO so it + * can't use it. + * The calculation of the used flag is slightly racy, as it may read + * desc, gc and pinctrl state without a lock covering all three at + * once. Worst case if the line is in transition and the calculation + * is inconsistent then it looks to the user like they performed the + * read on the other side of the transition - but that can always + * happen. + * The definitive test that a line is available to userspace is to + * request it. */ - info->flags = 0; - if (test_bit(FLAG_REQUESTED, &desc->flags) || - test_bit(FLAG_IS_HOGGED, &desc->flags) || - test_bit(FLAG_USED_AS_IRQ, &desc->flags) || - test_bit(FLAG_EXPORT, &desc->flags) || - test_bit(FLAG_SYSFS, &desc->flags) || + if (test_bit(FLAG_REQUESTED, &dflags) || + test_bit(FLAG_IS_HOGGED, &dflags) || + test_bit(FLAG_USED_AS_IRQ, &dflags) || + test_bit(FLAG_EXPORT, &dflags) || + test_bit(FLAG_SYSFS, &dflags) || !gpiochip_line_is_valid(gc, info->offset) || - !ok_for_pinctrl) + !pinctrl_gpio_can_use_line(gc, info->offset)) info->flags |= GPIO_V2_LINE_FLAG_USED; - if (test_bit(FLAG_IS_OUT, &desc->flags)) + if (test_bit(FLAG_IS_OUT, &dflags)) info->flags |= GPIO_V2_LINE_FLAG_OUTPUT; else info->flags |= GPIO_V2_LINE_FLAG_INPUT; - if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) + if (test_bit(FLAG_ACTIVE_LOW, &dflags)) info->flags |= GPIO_V2_LINE_FLAG_ACTIVE_LOW; - if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) + if (test_bit(FLAG_OPEN_DRAIN, &dflags)) info->flags |= GPIO_V2_LINE_FLAG_OPEN_DRAIN; - if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) + if (test_bit(FLAG_OPEN_SOURCE, &dflags)) info->flags |= GPIO_V2_LINE_FLAG_OPEN_SOURCE; - if (test_bit(FLAG_BIAS_DISABLE, &desc->flags)) + if (test_bit(FLAG_BIAS_DISABLE, &dflags)) info->flags |= GPIO_V2_LINE_FLAG_BIAS_DISABLED; - if (test_bit(FLAG_PULL_DOWN, &desc->flags)) + if (test_bit(FLAG_PULL_DOWN, &dflags)) info->flags |= GPIO_V2_LINE_FLAG_BIAS_PULL_DOWN; - if (test_bit(FLAG_PULL_UP, &desc->flags)) + if (test_bit(FLAG_PULL_UP, &dflags)) info->flags |= GPIO_V2_LINE_FLAG_BIAS_PULL_UP; - if (test_bit(FLAG_EDGE_RISING, &desc->flags)) + if (test_bit(FLAG_EDGE_RISING, &dflags)) info->flags |= GPIO_V2_LINE_FLAG_EDGE_RISING; - if (test_bit(FLAG_EDGE_FALLING, &desc->flags)) + if (test_bit(FLAG_EDGE_FALLING, &dflags)) info->flags |= GPIO_V2_LINE_FLAG_EDGE_FALLING; - if (test_bit(FLAG_EVENT_CLOCK_REALTIME, &desc->flags)) + if (test_bit(FLAG_EVENT_CLOCK_REALTIME, &dflags)) info->flags |= GPIO_V2_LINE_FLAG_EVENT_CLOCK_REALTIME; - else if (test_bit(FLAG_EVENT_CLOCK_HTE, &desc->flags)) + else if (test_bit(FLAG_EVENT_CLOCK_HTE, &dflags)) info->flags |= GPIO_V2_LINE_FLAG_EVENT_CLOCK_HTE; - - debounce_period_us = READ_ONCE(desc->debounce_period_us); - if (debounce_period_us) { - info->attrs[num_attrs].id = GPIO_V2_LINE_ATTR_ID_DEBOUNCE; - info->attrs[num_attrs].debounce_period_us = debounce_period_us; - num_attrs++; - } - info->num_attrs = num_attrs; - - spin_unlock_irqrestore(&gpio_lock, flags); } struct gpio_chardev_data { @@ -2455,6 +2571,7 @@ static int lineinfo_get(struct gpio_chardev_data *cdev, void __user *ip, return -EBUSY; } gpio_desc_to_lineinfo(desc, &lineinfo); + supinfo_to_lineinfo(desc, &lineinfo); if (copy_to_user(ip, &lineinfo, sizeof(lineinfo))) { if (watch) @@ -2553,6 +2670,7 @@ static int lineinfo_changed_notify(struct notifier_block *nb, chg.event_type = action; chg.timestamp_ns = ktime_get_ns(); gpio_desc_to_lineinfo(desc, &chg.info); + supinfo_to_lineinfo(desc, &chg.info); ret = kfifo_in_spinlocked(&cdev->events, &chg, 1, &cdev->wait.lock); if (ret) @@ -2621,38 +2739,30 @@ static ssize_t lineinfo_watch_read_unlocked(struct file *file, char __user *buf, #endif do { - spin_lock(&cdev->wait.lock); - if (kfifo_is_empty(&cdev->events)) { - if (bytes_read) { - spin_unlock(&cdev->wait.lock); - return bytes_read; + scoped_guard(spinlock, &cdev->wait.lock) { + if (kfifo_is_empty(&cdev->events)) { + if (bytes_read) + return bytes_read; + + if (file->f_flags & O_NONBLOCK) + return -EAGAIN; + + ret = wait_event_interruptible_locked(cdev->wait, + !kfifo_is_empty(&cdev->events)); + if (ret) + return ret; } - - if (file->f_flags & O_NONBLOCK) { - spin_unlock(&cdev->wait.lock); - return -EAGAIN; - } - - ret = wait_event_interruptible_locked(cdev->wait, - !kfifo_is_empty(&cdev->events)); - if (ret) { - spin_unlock(&cdev->wait.lock); - return ret; - } - } #ifdef CONFIG_GPIO_CDEV_V1 - /* must be after kfifo check so watch_abi_version is set */ - if (atomic_read(&cdev->watch_abi_version) == 2) - event_size = sizeof(struct gpio_v2_line_info_changed); - else - event_size = sizeof(struct gpioline_info_changed); - if (count < event_size) { - spin_unlock(&cdev->wait.lock); - return -EINVAL; - } + /* must be after kfifo check so watch_abi_version is set */ + if (atomic_read(&cdev->watch_abi_version) == 2) + event_size = sizeof(struct gpio_v2_line_info_changed); + else + event_size = sizeof(struct gpioline_info_changed); + if (count < event_size) + return -EINVAL; #endif - ret = kfifo_out(&cdev->events, &event, 1); - spin_unlock(&cdev->wait.lock); + ret = kfifo_out(&cdev->events, &event, 1); + } if (ret != 1) { ret = -EIO; break; diff --git a/drivers/gpio/gpiolib-sysfs.c b/drivers/gpio/gpiolib-sysfs.c index 12d853845bb8..1e91e7395d01 100644 --- a/drivers/gpio/gpiolib-sysfs.c +++ b/drivers/gpio/gpiolib-sysfs.c @@ -769,6 +769,25 @@ int gpiochip_sysfs_register(struct gpio_device *gdev) return 0; } +int gpiochip_sysfs_register_all(void) +{ + struct gpio_device *gdev; + int ret; + + guard(mutex)(&gpio_devices_lock); + + list_for_each_entry(gdev, &gpio_devices, list) { + if (gdev->mockdev) + continue; + + ret = gpiochip_sysfs_register(gdev); + if (ret) + return ret; + } + + return 0; +} + void gpiochip_sysfs_unregister(struct gpio_device *gdev) { struct gpio_desc *desc; @@ -793,9 +812,7 @@ void gpiochip_sysfs_unregister(struct gpio_device *gdev) static int __init gpiolib_sysfs_init(void) { - int status; - unsigned long flags; - struct gpio_device *gdev; + int status; status = class_register(&gpio_class); if (status < 0) @@ -807,26 +824,6 @@ static int __init gpiolib_sysfs_init(void) * We run before arch_initcall() so chip->dev nodes can have * registered, and so arch_initcall() can always gpiod_export(). */ - spin_lock_irqsave(&gpio_lock, flags); - list_for_each_entry(gdev, &gpio_devices, list) { - if (gdev->mockdev) - continue; - - /* - * TODO we yield gpio_lock here because - * gpiochip_sysfs_register() acquires a mutex. This is unsafe - * and needs to be fixed. - * - * Also it would be nice to use gpio_device_find() here so we - * can keep gpio_chips local to gpiolib.c, but the yield of - * gpio_lock prevents us from doing this. - */ - spin_unlock_irqrestore(&gpio_lock, flags); - status = gpiochip_sysfs_register(gdev); - spin_lock_irqsave(&gpio_lock, flags); - } - spin_unlock_irqrestore(&gpio_lock, flags); - - return status; + return gpiochip_sysfs_register_all(); } postcore_initcall(gpiolib_sysfs_init); diff --git a/drivers/gpio/gpiolib-sysfs.h b/drivers/gpio/gpiolib-sysfs.h index 0f213bdb4732..ab157cec0b4b 100644 --- a/drivers/gpio/gpiolib-sysfs.h +++ b/drivers/gpio/gpiolib-sysfs.h @@ -3,11 +3,12 @@ #ifndef GPIOLIB_SYSFS_H #define GPIOLIB_SYSFS_H -#ifdef CONFIG_GPIO_SYSFS - struct gpio_device; +#ifdef CONFIG_GPIO_SYSFS + int gpiochip_sysfs_register(struct gpio_device *gdev); +int gpiochip_sysfs_register_all(void); void gpiochip_sysfs_unregister(struct gpio_device *gdev); #else @@ -17,6 +18,11 @@ static inline int gpiochip_sysfs_register(struct gpio_device *gdev) return 0; } +static inline int gpiochip_sysfs_register_all(void) +{ + return 0; +} + static inline void gpiochip_sysfs_unregister(struct gpio_device *gdev) { } diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 95d2a7b2ea3e..c9ca809b55de 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -2,6 +2,7 @@ #include <linux/acpi.h> #include <linux/bitmap.h> +#include <linux/cleanup.h> #include <linux/compat.h> #include <linux/debugfs.h> #include <linux/device.h> @@ -15,6 +16,7 @@ #include <linux/kernel.h> #include <linux/list.h> #include <linux/module.h> +#include <linux/mutex.h> #include <linux/of.h> #include <linux/pinctrl/consumer.h> #include <linux/seq_file.h> @@ -94,7 +96,9 @@ DEFINE_SPINLOCK(gpio_lock); static DEFINE_MUTEX(gpio_lookup_lock); static LIST_HEAD(gpio_lookup_list); + LIST_HEAD(gpio_devices); +DEFINE_MUTEX(gpio_devices_lock); static DEFINE_MUTEX(gpio_machine_hogs_mutex); static LIST_HEAD(gpio_machine_hogs); @@ -126,20 +130,15 @@ static inline void desc_set_label(struct gpio_desc *d, const char *label) struct gpio_desc *gpio_to_desc(unsigned gpio) { struct gpio_device *gdev; - unsigned long flags; - - spin_lock_irqsave(&gpio_lock, flags); - list_for_each_entry(gdev, &gpio_devices, list) { - if (gdev->base <= gpio && - gdev->base + gdev->ngpio > gpio) { - spin_unlock_irqrestore(&gpio_lock, flags); - return &gdev->descs[gpio - gdev->base]; + scoped_guard(mutex, &gpio_devices_lock) { + list_for_each_entry(gdev, &gpio_devices, list) { + if (gdev->base <= gpio && + gdev->base + gdev->ngpio > gpio) + return &gdev->descs[gpio - gdev->base]; } } - spin_unlock_irqrestore(&gpio_lock, flags); - if (!gpio_is_valid(gpio)) pr_warn("invalid GPIO %d\n", gpio); @@ -255,6 +254,20 @@ int gpio_device_get_base(struct gpio_device *gdev) EXPORT_SYMBOL_GPL(gpio_device_get_base); /** + * gpio_device_get_label() - Get the label of this GPIO device + * @gdev: GPIO device + * + * Returns: + * Pointer to the string containing the GPIO device label. The string's + * lifetime is tied to that of the underlying GPIO device. + */ +const char *gpio_device_get_label(struct gpio_device *gdev) +{ + return gdev->label; +} +EXPORT_SYMBOL(gpio_device_get_label); + +/** * gpio_device_get_chip() - Get the gpio_chip implementation of this GPIO device * @gdev: GPIO device * @@ -276,7 +289,7 @@ struct gpio_chip *gpio_device_get_chip(struct gpio_device *gdev) EXPORT_SYMBOL_GPL(gpio_device_get_chip); /* dynamic allocation of GPIOs, e.g. on a hotplugged device */ -static int gpiochip_find_base(int ngpio) +static int gpiochip_find_base_unlocked(int ngpio) { struct gpio_device *gdev; int base = GPIO_DYNAMIC_BASE; @@ -349,7 +362,7 @@ EXPORT_SYMBOL_GPL(gpiod_get_direction); * Return -EBUSY if the new chip overlaps with some other chip's integer * space. */ -static int gpiodev_add_to_list(struct gpio_device *gdev) +static int gpiodev_add_to_list_unlocked(struct gpio_device *gdev) { struct gpio_device *prev, *next; @@ -398,26 +411,21 @@ static int gpiodev_add_to_list(struct gpio_device *gdev) static struct gpio_desc *gpio_name_to_desc(const char * const name) { struct gpio_device *gdev; - unsigned long flags; if (!name) return NULL; - spin_lock_irqsave(&gpio_lock, flags); + guard(mutex)(&gpio_devices_lock); list_for_each_entry(gdev, &gpio_devices, list) { struct gpio_desc *desc; for_each_gpio_desc(gdev->chip, desc) { - if (desc->name && !strcmp(desc->name, name)) { - spin_unlock_irqrestore(&gpio_lock, flags); + if (desc->name && !strcmp(desc->name, name)) return desc; - } } } - spin_unlock_irqrestore(&gpio_lock, flags); - return NULL; } @@ -655,11 +663,9 @@ EXPORT_SYMBOL_GPL(gpiochip_line_is_valid); static void gpiodev_release(struct device *dev) { struct gpio_device *gdev = to_gpio_device(dev); - unsigned long flags; - spin_lock_irqsave(&gpio_lock, flags); - list_del(&gdev->list); - spin_unlock_irqrestore(&gpio_lock, flags); + scoped_guard(mutex, &gpio_devices_lock) + list_del(&gdev->list); ida_free(&gpio_ida, gdev->id); kfree_const(gdev->label); @@ -817,7 +823,6 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data, struct lock_class_key *request_key) { struct gpio_device *gdev; - unsigned long flags; unsigned int i; int base = 0; int ret = 0; @@ -882,49 +887,46 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data, gdev->ngpio = gc->ngpio; - spin_lock_irqsave(&gpio_lock, flags); + scoped_guard(mutex, &gpio_devices_lock) { + /* + * TODO: this allocates a Linux GPIO number base in the global + * GPIO numberspace for this chip. In the long run we want to + * get *rid* of this numberspace and use only descriptors, but + * it may be a pipe dream. It will not happen before we get rid + * of the sysfs interface anyways. + */ + base = gc->base; - /* - * TODO: this allocates a Linux GPIO number base in the global - * GPIO numberspace for this chip. In the long run we want to - * get *rid* of this numberspace and use only descriptors, but - * it may be a pipe dream. It will not happen before we get rid - * of the sysfs interface anyways. - */ - base = gc->base; - if (base < 0) { - base = gpiochip_find_base(gc->ngpio); if (base < 0) { - spin_unlock_irqrestore(&gpio_lock, flags); - ret = base; - base = 0; + base = gpiochip_find_base_unlocked(gc->ngpio); + if (base < 0) { + ret = base; + base = 0; + goto err_free_label; + } + /* + * TODO: it should not be necessary to reflect the assigned + * base outside of the GPIO subsystem. Go over drivers and + * see if anyone makes use of this, else drop this and assign + * a poison instead. + */ + gc->base = base; + } else { + dev_warn(&gdev->dev, + "Static allocation of GPIO base is deprecated, use dynamic allocation.\n"); + } + gdev->base = base; + + ret = gpiodev_add_to_list_unlocked(gdev); + if (ret) { + chip_err(gc, "GPIO integer space overlap, cannot add chip\n"); goto err_free_label; } - /* - * TODO: it should not be necessary to reflect the assigned - * base outside of the GPIO subsystem. Go over drivers and - * see if anyone makes use of this, else drop this and assign - * a poison instead. - */ - gc->base = base; - } else { - dev_warn(&gdev->dev, - "Static allocation of GPIO base is deprecated, use dynamic allocation.\n"); - } - gdev->base = base; - ret = gpiodev_add_to_list(gdev); - if (ret) { - spin_unlock_irqrestore(&gpio_lock, flags); - chip_err(gc, "GPIO integer space overlap, cannot add chip\n"); - goto err_free_label; + for (i = 0; i < gc->ngpio; i++) + gdev->descs[i].gdev = gdev; } - for (i = 0; i < gc->ngpio; i++) - gdev->descs[i].gdev = gdev; - - spin_unlock_irqrestore(&gpio_lock, flags); - BLOCKING_INIT_NOTIFIER_HEAD(&gdev->line_state_notifier); BLOCKING_INIT_NOTIFIER_HEAD(&gdev->device_notifier); init_rwsem(&gdev->sem); @@ -1015,9 +1017,8 @@ err_free_gpiochip_mask: goto err_print_message; } err_remove_from_list: - spin_lock_irqsave(&gpio_lock, flags); - list_del(&gdev->list); - spin_unlock_irqrestore(&gpio_lock, flags); + scoped_guard(mutex, &gpio_devices_lock) + list_del(&gdev->list); err_free_label: kfree_const(gdev->label); err_free_descs: @@ -1071,7 +1072,7 @@ void gpiochip_remove(struct gpio_chip *gc) spin_lock_irqsave(&gpio_lock, flags); for (i = 0; i < gdev->ngpio; i++) { - if (gpiochip_is_requested(gc, i)) + if (test_bit(FLAG_REQUESTED, &gdev->descs[i].flags)) break; } spin_unlock_irqrestore(&gpio_lock, flags); @@ -1126,7 +1127,7 @@ struct gpio_device *gpio_device_find(void *data, */ might_sleep(); - guard(spinlock_irqsave)(&gpio_lock); + guard(mutex)(&gpio_devices_lock); list_for_each_entry(gdev, &gpio_devices, list) { if (gdev->chip && match(gdev->chip, data)) @@ -2331,9 +2332,6 @@ static bool gpiod_free_commit(struct gpio_desc *desc) #ifdef CONFIG_OF_DYNAMIC desc->hog = NULL; #endif -#ifdef CONFIG_GPIO_CDEV - WRITE_ONCE(desc->debounce_period_us, 0); -#endif ret = true; } @@ -2360,31 +2358,46 @@ void gpiod_free(struct gpio_desc *desc) } /** - * gpiochip_is_requested - return string iff signal was requested - * @gc: controller managing the signal - * @offset: of signal within controller's 0..(ngpio - 1) range + * gpiochip_dup_line_label - Get a copy of the consumer label. + * @gc: GPIO chip controlling this line. + * @offset: Hardware offset of the line. * - * Returns NULL if the GPIO is not currently requested, else a string. - * The string returned is the label passed to gpio_request(); if none has been - * passed it is a meaningless, non-NULL constant. + * Returns: + * Pointer to a copy of the consumer label if the line is requested or NULL + * if it's not. If a valid pointer was returned, it must be freed using + * kfree(). In case of a memory allocation error, the function returns %ENOMEM. * - * This function is for use by GPIO controller drivers. The label can - * help with diagnostics, and knowing that the signal is used as a GPIO - * can help avoid accidentally multiplexing it to another controller. + * Must not be called from atomic context. */ -const char *gpiochip_is_requested(struct gpio_chip *gc, unsigned int offset) +char *gpiochip_dup_line_label(struct gpio_chip *gc, unsigned int offset) { struct gpio_desc *desc; + char *label; desc = gpiochip_get_desc(gc, offset); if (IS_ERR(desc)) return NULL; - if (test_bit(FLAG_REQUESTED, &desc->flags) == 0) + guard(spinlock_irqsave)(&gpio_lock); + + if (!test_bit(FLAG_REQUESTED, &desc->flags)) return NULL; - return desc->label; + + /* + * FIXME: Once we mark gpiod_direction_input/output() and + * gpiod_get_direction() with might_sleep(), we'll be able to protect + * the GPIO descriptors with mutex (while value setting operations will + * become lockless). + * + * Until this happens, this allocation needs to be atomic. + */ + label = kstrdup(desc->label, GFP_ATOMIC); + if (!label) + return ERR_PTR(-ENOMEM); + + return label; } -EXPORT_SYMBOL_GPL(gpiochip_is_requested); +EXPORT_SYMBOL_GPL(gpiochip_dup_line_label); /** * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor @@ -4727,35 +4740,33 @@ static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev) static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos) { - unsigned long flags; struct gpio_device *gdev = NULL; loff_t index = *pos; s->private = ""; - spin_lock_irqsave(&gpio_lock, flags); - list_for_each_entry(gdev, &gpio_devices, list) - if (index-- == 0) { - spin_unlock_irqrestore(&gpio_lock, flags); + guard(mutex)(&gpio_devices_lock); + + list_for_each_entry(gdev, &gpio_devices, list) { + if (index-- == 0) return gdev; - } - spin_unlock_irqrestore(&gpio_lock, flags); + } return NULL; } static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos) { - unsigned long flags; struct gpio_device *gdev = v; void *ret = NULL; - spin_lock_irqsave(&gpio_lock, flags); - if (list_is_last(&gdev->list, &gpio_devices)) - ret = NULL; - else - ret = list_first_entry(&gdev->list, struct gpio_device, list); - spin_unlock_irqrestore(&gpio_lock, flags); + scoped_guard(mutex, &gpio_devices_lock) { + if (list_is_last(&gdev->list, &gpio_devices)) + ret = NULL; + else + ret = list_first_entry(&gdev->list, struct gpio_device, + list); + } s->private = "\n"; ++*pos; diff --git a/drivers/gpio/gpiolib.h b/drivers/gpio/gpiolib.h index 3ccacf3c1288..0ce7451a6b24 100644 --- a/drivers/gpio/gpiolib.h +++ b/drivers/gpio/gpiolib.h @@ -15,6 +15,7 @@ #include <linux/gpio/consumer.h> /* for enum gpiod_flags */ #include <linux/gpio/driver.h> #include <linux/module.h> +#include <linux/mutex.h> #include <linux/notifier.h> #include <linux/rwsem.h> @@ -136,6 +137,7 @@ int gpiod_set_transitory(struct gpio_desc *desc, bool transitory); extern spinlock_t gpio_lock; extern struct list_head gpio_devices; +extern struct mutex gpio_devices_lock; void gpiod_line_state_notify(struct gpio_desc *desc, unsigned long action); @@ -147,7 +149,6 @@ void gpiod_line_state_notify(struct gpio_desc *desc, unsigned long action); * @label: Name of the consumer * @name: Line name * @hog: Pointer to the device node that hogs this line (if any) - * @debounce_period_us: Debounce period in microseconds * * These are obtained using gpiod_get() and are preferable to the old * integer-based handles. @@ -185,10 +186,6 @@ struct gpio_desc { #ifdef CONFIG_OF_DYNAMIC struct device_node *hog; #endif -#ifdef CONFIG_GPIO_CDEV - /* debounce period in microseconds */ - unsigned int debounce_period_us; -#endif }; #define gpiod_not_found(desc) (IS_ERR(desc) && PTR_ERR(desc) == -ENOENT) |