diff options
| -rw-r--r-- | Documentation/devicetree/bindings/arm/bcm/raspberrypi,bcm2835-firmware.yaml | 20 | ||||
| -rw-r--r-- | drivers/clk/bcm/clk-raspberrypi.c | 2 | ||||
| -rw-r--r-- | drivers/firmware/raspberrypi.c | 69 | ||||
| -rw-r--r-- | drivers/gpio/gpio-raspberrypi-exp.c | 2 | ||||
| -rw-r--r-- | drivers/input/touchscreen/raspberrypi-ts.c | 2 | ||||
| -rw-r--r-- | drivers/pwm/Kconfig | 9 | ||||
| -rw-r--r-- | drivers/pwm/Makefile | 1 | ||||
| -rw-r--r-- | drivers/pwm/pwm-raspberrypi-poe.c | 206 | ||||
| -rw-r--r-- | drivers/reset/reset-raspberrypi.c | 2 | ||||
| -rw-r--r-- | drivers/soc/bcm/raspberrypi-power.c | 2 | ||||
| -rw-r--r-- | drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c | 2 | ||||
| -rw-r--r-- | include/dt-bindings/pwm/raspberrypi,firmware-poe-pwm.h | 13 | ||||
| -rw-r--r-- | include/soc/bcm2835/raspberrypi-firmware.h | 10 |
13 files changed, 331 insertions, 9 deletions
diff --git a/Documentation/devicetree/bindings/arm/bcm/raspberrypi,bcm2835-firmware.yaml b/Documentation/devicetree/bindings/arm/bcm/raspberrypi,bcm2835-firmware.yaml index a2c63c8b1d10..e3664eab0f6a 100644 --- a/Documentation/devicetree/bindings/arm/bcm/raspberrypi,bcm2835-firmware.yaml +++ b/Documentation/devicetree/bindings/arm/bcm/raspberrypi,bcm2835-firmware.yaml @@ -64,6 +64,21 @@ properties: - compatible - "#reset-cells" + pwm: + type: object + + properties: + compatible: + const: raspberrypi,firmware-poe-pwm + + "#pwm-cells": + # See pwm.yaml in this directory for a description of the cells format. + const: 2 + + required: + - compatible + - "#pwm-cells" + additionalProperties: false required: @@ -87,5 +102,10 @@ examples: compatible = "raspberrypi,firmware-reset"; #reset-cells = <1>; }; + + pwm: pwm { + compatible = "raspberrypi,firmware-poe-pwm"; + #pwm-cells = <2>; + }; }; ... diff --git a/drivers/clk/bcm/clk-raspberrypi.c b/drivers/clk/bcm/clk-raspberrypi.c index f89b9cfc4309..dd3b71eafabf 100644 --- a/drivers/clk/bcm/clk-raspberrypi.c +++ b/drivers/clk/bcm/clk-raspberrypi.c @@ -314,7 +314,7 @@ static int raspberrypi_clk_probe(struct platform_device *pdev) return -ENOENT; } - firmware = rpi_firmware_get(firmware_node); + firmware = devm_rpi_firmware_get(&pdev->dev, firmware_node); of_node_put(firmware_node); if (!firmware) return -EPROBE_DEFER; diff --git a/drivers/firmware/raspberrypi.c b/drivers/firmware/raspberrypi.c index 30259dc9b805..250e01680742 100644 --- a/drivers/firmware/raspberrypi.c +++ b/drivers/firmware/raspberrypi.c @@ -7,6 +7,7 @@ */ #include <linux/dma-mapping.h> +#include <linux/kref.h> #include <linux/mailbox_client.h> #include <linux/module.h> #include <linux/of_platform.h> @@ -27,6 +28,8 @@ struct rpi_firmware { struct mbox_chan *chan; /* The property channel. */ struct completion c; u32 enabled; + + struct kref consumers; }; static DEFINE_MUTEX(transaction_lock); @@ -225,12 +228,38 @@ static void rpi_register_clk_driver(struct device *dev) -1, NULL, 0); } +static void rpi_firmware_delete(struct kref *kref) +{ + struct rpi_firmware *fw = container_of(kref, struct rpi_firmware, + consumers); + + mbox_free_channel(fw->chan); + kfree(fw); +} + +void rpi_firmware_put(struct rpi_firmware *fw) +{ + kref_put(&fw->consumers, rpi_firmware_delete); +} +EXPORT_SYMBOL_GPL(rpi_firmware_put); + +static void devm_rpi_firmware_put(void *data) +{ + struct rpi_firmware *fw = data; + + rpi_firmware_put(fw); +} + static int rpi_firmware_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct rpi_firmware *fw; - fw = devm_kzalloc(dev, sizeof(*fw), GFP_KERNEL); + /* + * Memory will be freed by rpi_firmware_delete() once all users have + * released their firmware handles. Don't use devm_kzalloc() here. + */ + fw = kzalloc(sizeof(*fw), GFP_KERNEL); if (!fw) return -ENOMEM; @@ -247,6 +276,7 @@ static int rpi_firmware_probe(struct platform_device *pdev) } init_completion(&fw->c); + kref_init(&fw->consumers); platform_set_drvdata(pdev, fw); @@ -275,7 +305,8 @@ static int rpi_firmware_remove(struct platform_device *pdev) rpi_hwmon = NULL; platform_device_unregister(rpi_clk); rpi_clk = NULL; - mbox_free_channel(fw->chan); + + rpi_firmware_put(fw); return 0; } @@ -284,19 +315,51 @@ static int rpi_firmware_remove(struct platform_device *pdev) * rpi_firmware_get - Get pointer to rpi_firmware structure. * @firmware_node: Pointer to the firmware Device Tree node. * + * The reference to rpi_firmware has to be released with rpi_firmware_put(). + * * Returns NULL is the firmware device is not ready. */ struct rpi_firmware *rpi_firmware_get(struct device_node *firmware_node) { struct platform_device *pdev = of_find_device_by_node(firmware_node); + struct rpi_firmware *fw; if (!pdev) return NULL; - return platform_get_drvdata(pdev); + fw = platform_get_drvdata(pdev); + if (!fw) + return NULL; + + if (!kref_get_unless_zero(&fw->consumers)) + return NULL; + + return fw; } EXPORT_SYMBOL_GPL(rpi_firmware_get); +/** + * devm_rpi_firmware_get - Get pointer to rpi_firmware structure. + * @firmware_node: Pointer to the firmware Device Tree node. + * + * Returns NULL is the firmware device is not ready. + */ +struct rpi_firmware *devm_rpi_firmware_get(struct device *dev, + struct device_node *firmware_node) +{ + struct rpi_firmware *fw; + + fw = rpi_firmware_get(firmware_node); + if (!fw) + return NULL; + + if (devm_add_action_or_reset(dev, devm_rpi_firmware_put, fw)) + return NULL; + + return fw; +} +EXPORT_SYMBOL_GPL(devm_rpi_firmware_get); + static const struct of_device_id rpi_firmware_of_match[] = { { .compatible = "raspberrypi,bcm2835-firmware", }, {}, diff --git a/drivers/gpio/gpio-raspberrypi-exp.c b/drivers/gpio/gpio-raspberrypi-exp.c index bb100e0124e6..64a552ecc2ad 100644 --- a/drivers/gpio/gpio-raspberrypi-exp.c +++ b/drivers/gpio/gpio-raspberrypi-exp.c @@ -208,7 +208,7 @@ static int rpi_exp_gpio_probe(struct platform_device *pdev) return -ENOENT; } - fw = rpi_firmware_get(fw_node); + fw = devm_rpi_firmware_get(&pdev->dev, fw_node); of_node_put(fw_node); if (!fw) return -EPROBE_DEFER; diff --git a/drivers/input/touchscreen/raspberrypi-ts.c b/drivers/input/touchscreen/raspberrypi-ts.c index ef6aaed217cf..5000f5fd9ec3 100644 --- a/drivers/input/touchscreen/raspberrypi-ts.c +++ b/drivers/input/touchscreen/raspberrypi-ts.c @@ -160,7 +160,7 @@ static int rpi_ts_probe(struct platform_device *pdev) touchbuf = (u32)ts->fw_regs_phys; error = rpi_firmware_property(fw, RPI_FIRMWARE_FRAMEBUFFER_SET_TOUCHBUF, &touchbuf, sizeof(touchbuf)); - + rpi_firmware_put(fw); if (error || touchbuf != 0) { dev_warn(dev, "Failed to set touchbuf, %d\n", error); return error; diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig index 9a4f66ae8070..43d9f1884cd3 100644 --- a/drivers/pwm/Kconfig +++ b/drivers/pwm/Kconfig @@ -423,6 +423,15 @@ config PWM_PXA To compile this driver as a module, choose M here: the module will be called pwm-pxa. +config PWM_RASPBERRYPI_POE + tristate "Raspberry Pi Firwmware PoE Hat PWM support" + # Make sure not 'y' when RASPBERRYPI_FIRMWARE is 'm'. This can only + # happen when COMPILE_TEST=y, hence the added !RASPBERRYPI_FIRMWARE. + depends on RASPBERRYPI_FIRMWARE || (COMPILE_TEST && !RASPBERRYPI_FIRMWARE) + help + Enable Raspberry Pi firmware controller PWM bus used to control the + official RPI PoE hat + config PWM_RCAR tristate "Renesas R-Car PWM support" depends on ARCH_RENESAS || COMPILE_TEST diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile index 6374d3b1d6f3..211db810c439 100644 --- a/drivers/pwm/Makefile +++ b/drivers/pwm/Makefile @@ -38,6 +38,7 @@ obj-$(CONFIG_PWM_MXS) += pwm-mxs.o obj-$(CONFIG_PWM_OMAP_DMTIMER) += pwm-omap-dmtimer.o obj-$(CONFIG_PWM_PCA9685) += pwm-pca9685.o obj-$(CONFIG_PWM_PXA) += pwm-pxa.o +obj-$(CONFIG_PWM_RASPBERRYPI_POE) += pwm-raspberrypi-poe.o obj-$(CONFIG_PWM_RCAR) += pwm-rcar.o obj-$(CONFIG_PWM_RENESAS_TPU) += pwm-renesas-tpu.o obj-$(CONFIG_PWM_ROCKCHIP) += pwm-rockchip.o diff --git a/drivers/pwm/pwm-raspberrypi-poe.c b/drivers/pwm/pwm-raspberrypi-poe.c new file mode 100644 index 000000000000..043fc32e8be8 --- /dev/null +++ b/drivers/pwm/pwm-raspberrypi-poe.c @@ -0,0 +1,206 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright 2021 Nicolas Saenz Julienne <nsaenzjulienne@suse.de> + * For more information on Raspberry Pi's PoE hat see: + * https://www.raspberrypi.org/products/poe-hat/ + * + * Limitations: + * - No disable bit, so a disabled PWM is simulated by duty_cycle 0 + * - Only normal polarity + * - Fixed 12.5 kHz period + * + * The current period is completed when HW is reconfigured. + */ + +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/pwm.h> + +#include <soc/bcm2835/raspberrypi-firmware.h> +#include <dt-bindings/pwm/raspberrypi,firmware-poe-pwm.h> + +#define RPI_PWM_MAX_DUTY 255 +#define RPI_PWM_PERIOD_NS 80000 /* 12.5 kHz */ + +#define RPI_PWM_CUR_DUTY_REG 0x0 + +struct raspberrypi_pwm { + struct rpi_firmware *firmware; + struct pwm_chip chip; + unsigned int duty_cycle; +}; + +struct raspberrypi_pwm_prop { + __le32 reg; + __le32 val; + __le32 ret; +} __packed; + +static inline +struct raspberrypi_pwm *raspberrypi_pwm_from_chip(struct pwm_chip *chip) +{ + return container_of(chip, struct raspberrypi_pwm, chip); +} + +static int raspberrypi_pwm_set_property(struct rpi_firmware *firmware, + u32 reg, u32 val) +{ + struct raspberrypi_pwm_prop msg = { + .reg = cpu_to_le32(reg), + .val = cpu_to_le32(val), + }; + int ret; + + ret = rpi_firmware_property(firmware, RPI_FIRMWARE_SET_POE_HAT_VAL, + &msg, sizeof(msg)); + if (ret) + return ret; + if (msg.ret) + return -EIO; + + return 0; +} + +static int raspberrypi_pwm_get_property(struct rpi_firmware *firmware, + u32 reg, u32 *val) +{ + struct raspberrypi_pwm_prop msg = { + .reg = reg + }; + int ret; + + ret = rpi_firmware_property(firmware, RPI_FIRMWARE_GET_POE_HAT_VAL, + &msg, sizeof(msg)); + if (ret) + return ret; + if (msg.ret) + return -EIO; + + *val = le32_to_cpu(msg.val); + + return 0; +} + +static void raspberrypi_pwm_get_state(struct pwm_chip *chip, + struct pwm_device *pwm, + struct pwm_state *state) +{ + struct raspberrypi_pwm *rpipwm = raspberrypi_pwm_from_chip(chip); + + state->period = RPI_PWM_PERIOD_NS; + state->duty_cycle = DIV_ROUND_UP(rpipwm->duty_cycle * RPI_PWM_PERIOD_NS, + RPI_PWM_MAX_DUTY); + state->enabled = !!(rpipwm->duty_cycle); + state->polarity = PWM_POLARITY_NORMAL; +} + +static int raspberrypi_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, + const struct pwm_state *state) +{ + struct raspberrypi_pwm *rpipwm = raspberrypi_pwm_from_chip(chip); + unsigned int duty_cycle; + int ret; + + if (state->period < RPI_PWM_PERIOD_NS || + state->polarity != PWM_POLARITY_NORMAL) + return -EINVAL; + + if (!state->enabled) + duty_cycle = 0; + else if (state->duty_cycle < RPI_PWM_PERIOD_NS) + duty_cycle = DIV_ROUND_DOWN_ULL(state->duty_cycle * RPI_PWM_MAX_DUTY, + RPI_PWM_PERIOD_NS); + else + duty_cycle = RPI_PWM_MAX_DUTY; + + if (duty_cycle == rpipwm->duty_cycle) + return 0; + + ret = raspberrypi_pwm_set_property(rpipwm->firmware, RPI_PWM_CUR_DUTY_REG, + duty_cycle); + if (ret) { + dev_err(chip->dev, "Failed to set duty cycle: %pe\n", + ERR_PTR(ret)); + return ret; + } + + rpipwm->duty_cycle = duty_cycle; + + return 0; +} + +static const struct pwm_ops raspberrypi_pwm_ops = { + .get_state = raspberrypi_pwm_get_state, + .apply = raspberrypi_pwm_apply, + .owner = THIS_MODULE, +}; + +static int raspberrypi_pwm_probe(struct platform_device *pdev) +{ + struct device_node *firmware_node; + struct device *dev = &pdev->dev; + struct rpi_firmware *firmware; + struct raspberrypi_pwm *rpipwm; + int ret; + + firmware_node = of_get_parent(dev->of_node); + if (!firmware_node) { + dev_err(dev, "Missing firmware node\n"); + return -ENOENT; + } + + firmware = devm_rpi_firmware_get(&pdev->dev, firmware_node); + of_node_put(firmware_node); + if (!firmware) + return dev_err_probe(dev, -EPROBE_DEFER, + "Failed to get firmware handle\n"); + + rpipwm = devm_kzalloc(&pdev->dev, sizeof(*rpipwm), GFP_KERNEL); + if (!rpipwm) + return -ENOMEM; + + rpipwm->firmware = firmware; + rpipwm->chip.dev = dev; + rpipwm->chip.ops = &raspberrypi_pwm_ops; + rpipwm->chip.base = -1; + rpipwm->chip.npwm = RASPBERRYPI_FIRMWARE_PWM_NUM; + + platform_set_drvdata(pdev, rpipwm); + + ret = raspberrypi_pwm_get_property(rpipwm->firmware, RPI_PWM_CUR_DUTY_REG, + &rpipwm->duty_cycle); + if (ret) { + dev_err(dev, "Failed to get duty cycle: %pe\n", ERR_PTR(ret)); + return ret; + } + + return pwmchip_add(&rpipwm->chip); +} + +static int raspberrypi_pwm_remove(struct platform_device *pdev) +{ + struct raspberrypi_pwm *rpipwm = platform_get_drvdata(pdev); + + return pwmchip_remove(&rpipwm->chip); +} + +static const struct of_device_id raspberrypi_pwm_of_match[] = { + { .compatible = "raspberrypi,firmware-poe-pwm", }, + { } +}; +MODULE_DEVICE_TABLE(of, raspberrypi_pwm_of_match); + +static struct platform_driver raspberrypi_pwm_driver = { + .driver = { + .name = "raspberrypi-poe-pwm", + .of_match_table = raspberrypi_pwm_of_match, + }, + .probe = raspberrypi_pwm_probe, + .remove = raspberrypi_pwm_remove, +}; +module_platform_driver(raspberrypi_pwm_driver); + +MODULE_AUTHOR("Nicolas Saenz Julienne <nsaenzjulienne@suse.de>"); +MODULE_DESCRIPTION("Raspberry Pi Firmware Based PWM Bus Driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/reset/reset-raspberrypi.c b/drivers/reset/reset-raspberrypi.c index 02f59c06f69b..fa23db554bcf 100644 --- a/drivers/reset/reset-raspberrypi.c +++ b/drivers/reset/reset-raspberrypi.c @@ -82,7 +82,7 @@ static int rpi_reset_probe(struct platform_device *pdev) return -ENOENT; } - fw = rpi_firmware_get(np); + fw = devm_rpi_firmware_get(&pdev->dev, np); of_node_put(np); if (!fw) return -EPROBE_DEFER; diff --git a/drivers/soc/bcm/raspberrypi-power.c b/drivers/soc/bcm/raspberrypi-power.c index 5d1aacdd84ef..068715d6e66d 100644 --- a/drivers/soc/bcm/raspberrypi-power.c +++ b/drivers/soc/bcm/raspberrypi-power.c @@ -177,7 +177,7 @@ static int rpi_power_probe(struct platform_device *pdev) return -ENODEV; } - rpi_domains->fw = rpi_firmware_get(fw_np); + rpi_domains->fw = devm_rpi_firmware_get(&pdev->dev, fw_np); of_node_put(fw_np); if (!rpi_domains->fw) return -EPROBE_DEFER; diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c index 59e45dc03a97..f27072837247 100644 --- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c +++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c @@ -2734,7 +2734,7 @@ static int vchiq_probe(struct platform_device *pdev) return -ENOENT; } - drvdata->fw = rpi_firmware_get(fw_node); + drvdata->fw = devm_rpi_firmware_get(&pdev->dev, fw_node); of_node_put(fw_node); if (!drvdata->fw) return -EPROBE_DEFER; diff --git a/include/dt-bindings/pwm/raspberrypi,firmware-poe-pwm.h b/include/dt-bindings/pwm/raspberrypi,firmware-poe-pwm.h new file mode 100644 index 000000000000..27c5ce68847b --- /dev/null +++ b/include/dt-bindings/pwm/raspberrypi,firmware-poe-pwm.h @@ -0,0 +1,13 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (c) 2020 Nicolas Saenz Julienne + * Author: Nicolas Saenz Julienne <nsaenzjulienne@suse.de> + */ + +#ifndef _DT_BINDINGS_RASPBERRYPI_FIRMWARE_PWM_H +#define _DT_BINDINGS_RASPBERRYPI_FIRMWARE_PWM_H + +#define RASPBERRYPI_FIRMWARE_PWM_POE 0 +#define RASPBERRYPI_FIRMWARE_PWM_NUM 1 + +#endif diff --git a/include/soc/bcm2835/raspberrypi-firmware.h b/include/soc/bcm2835/raspberrypi-firmware.h index cc9cdbc66403..73ad784fca96 100644 --- a/include/soc/bcm2835/raspberrypi-firmware.h +++ b/include/soc/bcm2835/raspberrypi-firmware.h @@ -140,7 +140,10 @@ int rpi_firmware_property(struct rpi_firmware *fw, u32 tag, void *data, size_t len); int rpi_firmware_property_list(struct rpi_firmware *fw, void *data, size_t tag_size); +void rpi_firmware_put(struct rpi_firmware *fw); struct rpi_firmware *rpi_firmware_get(struct device_node *firmware_node); +struct rpi_firmware *devm_rpi_firmware_get(struct device *dev, + struct device_node *firmware_node); #else static inline int rpi_firmware_property(struct rpi_firmware *fw, u32 tag, void *data, size_t len) @@ -154,10 +157,17 @@ static inline int rpi_firmware_property_list(struct rpi_firmware *fw, return -ENOSYS; } +static inline void rpi_firmware_put(struct rpi_firmware *fw) { } static inline struct rpi_firmware *rpi_firmware_get(struct device_node *firmware_node) { return NULL; } + +static inline struct rpi_firmware *devm_rpi_firmware_get(struct device *dev, + struct device_node *firmware_node) +{ + return NULL; +} #endif #endif /* __SOC_RASPBERRY_FIRMWARE_H__ */ |