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authorBruno Randolf <br1@einfach.org>2013-12-05 03:56:43 +0400
committerLinus Walleij <linus.walleij@linaro.org>2013-12-20 13:08:23 +0400
commit12262bef8f4614df7af8b2963de5beddee18ae5e (patch)
tree8a1a6cc77e6be5c81cd24d861d59510adefa65b5 /drivers/gpio/gpio-sch311x.c
parenta00580c2809f44fd1d284bf2638395a261d28cc9 (diff)
downloadlinux-12262bef8f4614df7af8b2963de5beddee18ae5e.tar.xz
gpio: add GPIO support for SMSC SCH311x
This patch adds support for the GPIOs found on the SMSC "Super I/ SCH311x. The chip detection and I/O functions are copied from sch311x_wdt. Signed-off-by: Bruno Randolf <br1@einfach.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'drivers/gpio/gpio-sch311x.c')
-rw-r--r--drivers/gpio/gpio-sch311x.c431
1 files changed, 431 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-sch311x.c b/drivers/gpio/gpio-sch311x.c
new file mode 100644
index 000000000000..483a6f8bd958
--- /dev/null
+++ b/drivers/gpio/gpio-sch311x.c
@@ -0,0 +1,431 @@
+/*
+ * GPIO driver for the SMSC SCH311x Super-I/O chips
+ *
+ * Copyright (C) 2013 Bruno Randolf <br1@einfach.org>
+ *
+ * SuperIO functions and chip detection:
+ * (c) Copyright 2008 Wim Van Sebroeck <wim@iguana.be>.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/gpio.h>
+#include <linux/bitops.h>
+
+#define DRV_NAME "gpio-sch311x"
+
+#define SCH311X_GPIO_CONF_OUT 0x00
+#define SCH311X_GPIO_CONF_IN 0x01
+#define SCH311X_GPIO_CONF_INVERT 0x02
+#define SCH311X_GPIO_CONF_OPEN_DRAIN 0x80
+
+#define SIO_CONFIG_KEY_ENTER 0x55
+#define SIO_CONFIG_KEY_EXIT 0xaa
+
+#define GP1 0x4b
+
+static int sch311x_ioports[] = { 0x2e, 0x4e, 0x162e, 0x164e };
+
+static struct platform_device *sch311x_gpio_pdev;
+
+struct sch311x_pdev_data { /* platform device data */
+ unsigned short runtime_reg; /* runtime register base address */
+};
+
+struct sch311x_gpio_block { /* one GPIO block runtime data */
+ struct gpio_chip chip;
+ unsigned short data_reg; /* from definition below */
+ unsigned short *config_regs; /* pointer to definition below */
+ unsigned short runtime_reg; /* runtime register */
+ spinlock_t lock; /* lock for this GPIO block */
+};
+
+struct sch311x_gpio_priv { /* driver private data */
+ struct sch311x_gpio_block blocks[6];
+};
+
+struct sch311x_gpio_block_def { /* register address definitions */
+ unsigned short data_reg;
+ unsigned short config_regs[8];
+ unsigned short base;
+};
+
+/* Note: some GPIOs are not available, these are marked with 0x00 */
+
+static struct sch311x_gpio_block_def sch311x_gpio_blocks[] = {
+ {
+ .data_reg = 0x4b, /* GP1 */
+ .config_regs = {0x23, 0x24, 0x25, 0x26, 0x27, 0x29, 0x2a, 0x2b},
+ .base = 10,
+ },
+ {
+ .data_reg = 0x4c, /* GP2 */
+ .config_regs = {0x00, 0x2c, 0x2d, 0x00, 0x00, 0x00, 0x00, 0x32},
+ .base = 20,
+ },
+ {
+ .data_reg = 0x4d, /* GP3 */
+ .config_regs = {0x33, 0x34, 0x35, 0x36, 0x37, 0x00, 0x39, 0x3a},
+ .base = 30,
+ },
+ {
+ .data_reg = 0x4e, /* GP4 */
+ .config_regs = {0x3b, 0x00, 0x3d, 0x00, 0x6e, 0x6f, 0x72, 0x73},
+ .base = 40,
+ },
+ {
+ .data_reg = 0x4f, /* GP5 */
+ .config_regs = {0x3f, 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46},
+ .base = 50,
+ },
+ {
+ .data_reg = 0x50, /* GP6 */
+ .config_regs = {0x47, 0x48, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59},
+ .base = 60,
+ },
+};
+
+static inline struct sch311x_gpio_block *
+to_sch311x_gpio_block(struct gpio_chip *chip)
+{
+ return container_of(chip, struct sch311x_gpio_block, chip);
+}
+
+
+/*
+ * Super-IO functions
+ */
+
+static inline int sch311x_sio_enter(int sio_config_port)
+{
+ /* Don't step on other drivers' I/O space by accident. */
+ if (!request_muxed_region(sio_config_port, 2, DRV_NAME)) {
+ pr_err(DRV_NAME "I/O address 0x%04x already in use\n",
+ sio_config_port);
+ return -EBUSY;
+ }
+
+ outb(SIO_CONFIG_KEY_ENTER, sio_config_port);
+ return 0;
+}
+
+static inline void sch311x_sio_exit(int sio_config_port)
+{
+ outb(SIO_CONFIG_KEY_EXIT, sio_config_port);
+ release_region(sio_config_port, 2);
+}
+
+static inline int sch311x_sio_inb(int sio_config_port, int reg)
+{
+ outb(reg, sio_config_port);
+ return inb(sio_config_port + 1);
+}
+
+static inline void sch311x_sio_outb(int sio_config_port, int reg, int val)
+{
+ outb(reg, sio_config_port);
+ outb(val, sio_config_port + 1);
+}
+
+
+/*
+ * GPIO functions
+ */
+
+static int sch311x_gpio_request(struct gpio_chip *chip, unsigned offset)
+{
+ struct sch311x_gpio_block *block = to_sch311x_gpio_block(chip);
+
+ if (block->config_regs[offset] == 0) /* GPIO is not available */
+ return -ENODEV;
+
+ if (!request_region(block->runtime_reg + block->config_regs[offset],
+ 1, DRV_NAME)) {
+ dev_err(chip->dev, "Failed to request region 0x%04x.\n",
+ block->runtime_reg + block->config_regs[offset]);
+ return -EBUSY;
+ }
+ return 0;
+}
+
+static void sch311x_gpio_free(struct gpio_chip *chip, unsigned offset)
+{
+ struct sch311x_gpio_block *block = to_sch311x_gpio_block(chip);
+
+ if (block->config_regs[offset] == 0) /* GPIO is not available */
+ return;
+
+ release_region(block->runtime_reg + block->config_regs[offset], 1);
+}
+
+static int sch311x_gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+ struct sch311x_gpio_block *block = to_sch311x_gpio_block(chip);
+ unsigned char data;
+
+ spin_lock(&block->lock);
+ data = inb(block->runtime_reg + block->data_reg);
+ spin_unlock(&block->lock);
+
+ return !!(data & BIT(offset));
+}
+
+static void __sch311x_gpio_set(struct sch311x_gpio_block *block,
+ unsigned offset, int value)
+{
+ unsigned char data = inb(block->runtime_reg + block->data_reg);
+ if (value)
+ data |= BIT(offset);
+ else
+ data &= ~BIT(offset);
+ outb(data, block->runtime_reg + block->data_reg);
+}
+
+static void sch311x_gpio_set(struct gpio_chip *chip, unsigned offset,
+ int value)
+{
+ struct sch311x_gpio_block *block = to_sch311x_gpio_block(chip);
+
+ spin_lock(&block->lock);
+ __sch311x_gpio_set(block, offset, value);
+ spin_unlock(&block->lock);
+}
+
+static int sch311x_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
+{
+ struct sch311x_gpio_block *block = to_sch311x_gpio_block(chip);
+
+ spin_lock(&block->lock);
+ outb(SCH311X_GPIO_CONF_IN, block->runtime_reg +
+ block->config_regs[offset]);
+ spin_unlock(&block->lock);
+
+ return 0;
+}
+
+static int sch311x_gpio_direction_out(struct gpio_chip *chip, unsigned offset,
+ int value)
+{
+ struct sch311x_gpio_block *block = to_sch311x_gpio_block(chip);
+
+ spin_lock(&block->lock);
+
+ outb(SCH311X_GPIO_CONF_OUT, block->runtime_reg +
+ block->config_regs[offset]);
+
+ __sch311x_gpio_set(block, offset, value);
+
+ spin_unlock(&block->lock);
+ return 0;
+}
+
+static int sch311x_gpio_probe(struct platform_device *pdev)
+{
+ struct sch311x_pdev_data *pdata = pdev->dev.platform_data;
+ struct sch311x_gpio_priv *priv;
+ struct sch311x_gpio_block *block;
+ int err, i;
+
+ /* we can register all GPIO data registers at once */
+ if (!request_region(pdata->runtime_reg + GP1, 6, DRV_NAME)) {
+ dev_err(&pdev->dev, "Failed to request region 0x%04x-0x%04x.\n",
+ pdata->runtime_reg + GP1, pdata->runtime_reg + GP1 + 5);
+ return -EBUSY;
+ }
+
+ priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, priv);
+
+ for (i = 0; i < ARRAY_SIZE(priv->blocks); i++) {
+ block = &priv->blocks[i];
+
+ spin_lock_init(&block->lock);
+
+ block->chip.label = DRV_NAME;
+ block->chip.owner = THIS_MODULE;
+ block->chip.request = sch311x_gpio_request;
+ block->chip.free = sch311x_gpio_free;
+ block->chip.direction_input = sch311x_gpio_direction_in;
+ block->chip.direction_output = sch311x_gpio_direction_out;
+ block->chip.get = sch311x_gpio_get;
+ block->chip.set = sch311x_gpio_set;
+ block->chip.ngpio = 8;
+ block->chip.dev = &pdev->dev;
+ block->chip.base = sch311x_gpio_blocks[i].base;
+ block->config_regs = sch311x_gpio_blocks[i].config_regs;
+ block->data_reg = sch311x_gpio_blocks[i].data_reg;
+ block->runtime_reg = pdata->runtime_reg;
+
+ err = gpiochip_add(&block->chip);
+ if (err < 0) {
+ dev_err(&pdev->dev,
+ "Could not register gpiochip, %d\n", err);
+ goto exit_err;
+ }
+ dev_info(&pdev->dev,
+ "SMSC SCH311x GPIO block %d registered.\n", i);
+ }
+
+ return 0;
+
+exit_err:
+ release_region(pdata->runtime_reg + GP1, 6);
+ /* release already registered chips */
+ for (--i; i >= 0; i--)
+ gpiochip_remove(&priv->blocks[i].chip);
+ return err;
+}
+
+static int sch311x_gpio_remove(struct platform_device *pdev)
+{
+ struct sch311x_pdev_data *pdata = pdev->dev.platform_data;
+ struct sch311x_gpio_priv *priv = platform_get_drvdata(pdev);
+ int err, i;
+
+ release_region(pdata->runtime_reg + GP1, 6);
+
+ for (i = 0; i < ARRAY_SIZE(priv->blocks); i++) {
+ err = gpiochip_remove(&priv->blocks[i].chip);
+ if (err)
+ return err;
+ dev_info(&pdev->dev,
+ "SMSC SCH311x GPIO block %d unregistered.\n", i);
+ }
+ return 0;
+}
+
+static struct platform_driver sch311x_gpio_driver = {
+ .driver.name = DRV_NAME,
+ .driver.owner = THIS_MODULE,
+ .probe = sch311x_gpio_probe,
+ .remove = sch311x_gpio_remove,
+};
+
+
+/*
+ * Init & exit routines
+ */
+
+static int __init sch311x_detect(int sio_config_port, unsigned short *addr)
+{
+ int err = 0, reg;
+ unsigned short base_addr;
+ unsigned char dev_id;
+
+ err = sch311x_sio_enter(sio_config_port);
+ if (err)
+ return err;
+
+ /* Check device ID. We currently know about:
+ * SCH3112 (0x7c), SCH3114 (0x7d), and SCH3116 (0x7f). */
+ reg = sch311x_sio_inb(sio_config_port, 0x20);
+ if (!(reg == 0x7c || reg == 0x7d || reg == 0x7f)) {
+ err = -ENODEV;
+ goto exit;
+ }
+ dev_id = reg == 0x7c ? 2 : reg == 0x7d ? 4 : 6;
+
+ /* Select logical device A (runtime registers) */
+ sch311x_sio_outb(sio_config_port, 0x07, 0x0a);
+
+ /* Check if Logical Device Register is currently active */
+ if ((sch311x_sio_inb(sio_config_port, 0x30) & 0x01) == 0)
+ pr_info("Seems that LDN 0x0a is not active...\n");
+
+ /* Get the base address of the runtime registers */
+ base_addr = (sch311x_sio_inb(sio_config_port, 0x60) << 8) |
+ sch311x_sio_inb(sio_config_port, 0x61);
+ if (!base_addr) {
+ pr_err("Base address not set\n");
+ err = -ENODEV;
+ goto exit;
+ }
+ *addr = base_addr;
+
+ pr_info("Found an SMSC SCH311%d chip at 0x%04x\n", dev_id, base_addr);
+
+exit:
+ sch311x_sio_exit(sio_config_port);
+ return err;
+}
+
+static int __init sch311x_gpio_pdev_add(const unsigned short addr)
+{
+ struct sch311x_pdev_data pdata;
+ int err;
+
+ pdata.runtime_reg = addr;
+
+ sch311x_gpio_pdev = platform_device_alloc(DRV_NAME, -1);
+ if (!sch311x_gpio_pdev)
+ return -ENOMEM;
+
+ err = platform_device_add_data(sch311x_gpio_pdev,
+ &pdata, sizeof(pdata));
+ if (err) {
+ pr_err(DRV_NAME "Platform data allocation failed\n");
+ goto err;
+ }
+
+ err = platform_device_add(sch311x_gpio_pdev);
+ if (err) {
+ pr_err(DRV_NAME "Device addition failed\n");
+ goto err;
+ }
+ return 0;
+
+err:
+ platform_device_put(sch311x_gpio_pdev);
+ return err;
+}
+
+static int __init sch311x_gpio_init(void)
+{
+ int err, i;
+ unsigned short addr = 0;
+
+ for (i = 0; i < ARRAY_SIZE(sch311x_ioports); i++)
+ if (sch311x_detect(sch311x_ioports[i], &addr) == 0)
+ break;
+
+ if (!addr)
+ return -ENODEV;
+
+ err = platform_driver_register(&sch311x_gpio_driver);
+ if (err)
+ return err;
+
+ err = sch311x_gpio_pdev_add(addr);
+ if (err)
+ goto unreg_platform_driver;
+
+ return 0;
+
+unreg_platform_driver:
+ platform_driver_unregister(&sch311x_gpio_driver);
+ return err;
+}
+
+static void __exit sch311x_gpio_exit(void)
+{
+ platform_device_unregister(sch311x_gpio_pdev);
+ platform_driver_unregister(&sch311x_gpio_driver);
+}
+
+module_init(sch311x_gpio_init);
+module_exit(sch311x_gpio_exit);
+
+MODULE_AUTHOR("Bruno Randolf <br1@einfach.org>");
+MODULE_DESCRIPTION("SMSC SCH311x GPIO Driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:gpio-sch311x");