From e5a06dc5ac1f686d11b11488a88a63ab12e079cb Mon Sep 17 00:00:00 2001 From: Bart Tanghe Date: Wed, 8 Oct 2014 12:14:32 +0200 Subject: pwm: Add BCM2835 PWM driver Add PWM driver for Broadcom BCM2835 processor (Raspberry Pi) Signed-off-by: Bart Tanghe Acked-by: Stephen Warren Signed-off-by: Thierry Reding diff --git a/Documentation/devicetree/bindings/pwm/pwm-bcm2835.txt b/Documentation/devicetree/bindings/pwm/pwm-bcm2835.txt new file mode 100644 index 0000000..fb6fb31 --- /dev/null +++ b/Documentation/devicetree/bindings/pwm/pwm-bcm2835.txt @@ -0,0 +1,30 @@ +BCM2835 PWM controller (Raspberry Pi controller) + +Required properties: +- compatible: should be "brcm,bcm2835-pwm" +- reg: physical base address and length of the controller's registers +- clock: This clock defines the base clock frequency of the PWM hardware + system, the period and the duty_cycle of the PWM signal is a multiple of + the base period. +- #pwm-cells: Should be 2. See pwm.txt in this directory for a description of + the cells format. + +Examples: + +pwm@2020c000 { + compatible = "brcm,bcm2835-pwm"; + reg = <0x2020c000 0x28>; + clocks = <&clk_pwm>; + #pwm-cells = <2>; +}; + +clocks { + .... + clk_pwm: pwm { + compatible = "fixed-clock"; + reg = <3>; + #clock-cells = <0>; + clock-frequency = <9200000>; + }; + .... +}; diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig index ef2dd2e..ddabe39 100644 --- a/drivers/pwm/Kconfig +++ b/drivers/pwm/Kconfig @@ -71,6 +71,15 @@ config PWM_BCM_KONA To compile this driver as a module, choose M here: the module will be called pwm-bcm-kona. +config PWM_BCM2835 + tristate "BCM2835 PWM support" + depends on ARCH_BCM2835 + help + PWM framework driver for BCM2835 controller (Raspberry Pi) + + To compile this driver as a module, choose M here: the module + will be called pwm-bcm2835. + config PWM_BFIN tristate "Blackfin PWM support" depends on BFIN_GPTIMERS diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile index c458606..88be33b 100644 --- a/drivers/pwm/Makefile +++ b/drivers/pwm/Makefile @@ -4,6 +4,7 @@ obj-$(CONFIG_PWM_AB8500) += pwm-ab8500.o obj-$(CONFIG_PWM_ATMEL) += pwm-atmel.o obj-$(CONFIG_PWM_ATMEL_TCB) += pwm-atmel-tcb.o obj-$(CONFIG_PWM_BCM_KONA) += pwm-bcm-kona.o +obj-$(CONFIG_PWM_BCM2835) += pwm-bcm2835.o obj-$(CONFIG_PWM_BFIN) += pwm-bfin.o obj-$(CONFIG_PWM_CLPS711X) += pwm-clps711x.o obj-$(CONFIG_PWM_EP93XX) += pwm-ep93xx.o diff --git a/drivers/pwm/pwm-bcm2835.c b/drivers/pwm/pwm-bcm2835.c new file mode 100644 index 0000000..b4c7f95 --- /dev/null +++ b/drivers/pwm/pwm-bcm2835.c @@ -0,0 +1,205 @@ +/* + * Copyright 2014 Bart Tanghe + * + * 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; version 2. + */ + +#include +#include +#include +#include +#include +#include +#include + +#define PWM_CONTROL 0x000 +#define PWM_CONTROL_SHIFT(x) ((x) * 8) +#define PWM_CONTROL_MASK 0xff +#define PWM_MODE 0x80 /* set timer in PWM mode */ +#define PWM_ENABLE (1 << 0) +#define PWM_POLARITY (1 << 4) + +#define PERIOD(x) (((x) * 0x10) + 0x10) +#define DUTY(x) (((x) * 0x10) + 0x14) + +#define MIN_PERIOD 108 /* 9.2 MHz max. PWM clock */ + +struct bcm2835_pwm { + struct pwm_chip chip; + struct device *dev; + unsigned long scaler; + void __iomem *base; + struct clk *clk; +}; + +static inline struct bcm2835_pwm *to_bcm2835_pwm(struct pwm_chip *chip) +{ + return container_of(chip, struct bcm2835_pwm, chip); +} + +static int bcm2835_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm) +{ + struct bcm2835_pwm *pc = to_bcm2835_pwm(chip); + u32 value; + + value = readl(pc->base + PWM_CONTROL); + value &= ~(PWM_CONTROL_MASK << PWM_CONTROL_SHIFT(pwm->hwpwm)); + value |= (PWM_MODE << PWM_CONTROL_SHIFT(pwm->hwpwm)); + writel(value, pc->base + PWM_CONTROL); + + return 0; +} + +static void bcm2835_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm) +{ + struct bcm2835_pwm *pc = to_bcm2835_pwm(chip); + u32 value; + + value = readl(pc->base + PWM_CONTROL); + value &= ~(PWM_CONTROL_MASK << PWM_CONTROL_SHIFT(pwm->hwpwm)); + writel(value, pc->base + PWM_CONTROL); +} + +static int bcm2835_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, + int duty_ns, int period_ns) +{ + struct bcm2835_pwm *pc = to_bcm2835_pwm(chip); + + if (period_ns <= MIN_PERIOD) { + dev_err(pc->dev, "period %d not supported, minimum %d\n", + period_ns, MIN_PERIOD); + return -EINVAL; + } + + writel(duty_ns / pc->scaler, pc->base + DUTY(pwm->hwpwm)); + writel(period_ns / pc->scaler, pc->base + PERIOD(pwm->hwpwm)); + + return 0; +} + +static int bcm2835_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) +{ + struct bcm2835_pwm *pc = to_bcm2835_pwm(chip); + u32 value; + + value = readl(pc->base + PWM_CONTROL); + value |= PWM_ENABLE << PWM_CONTROL_SHIFT(pwm->hwpwm); + writel(value, pc->base + PWM_CONTROL); + + return 0; +} + +static void bcm2835_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) +{ + struct bcm2835_pwm *pc = to_bcm2835_pwm(chip); + u32 value; + + value = readl(pc->base + PWM_CONTROL); + value &= ~(PWM_ENABLE << PWM_CONTROL_SHIFT(pwm->hwpwm)); + writel(value, pc->base + PWM_CONTROL); +} + +static int bcm2835_set_polarity(struct pwm_chip *chip, struct pwm_device *pwm, + enum pwm_polarity polarity) +{ + struct bcm2835_pwm *pc = to_bcm2835_pwm(chip); + u32 value; + + value = readl(pc->base + PWM_CONTROL); + + if (polarity == PWM_POLARITY_NORMAL) + value &= ~(PWM_POLARITY << PWM_CONTROL_SHIFT(pwm->hwpwm)); + else + value |= PWM_POLARITY << PWM_CONTROL_SHIFT(pwm->hwpwm); + + writel(value, pc->base + PWM_CONTROL); + + return 0; +} + +static const struct pwm_ops bcm2835_pwm_ops = { + .request = bcm2835_pwm_request, + .free = bcm2835_pwm_free, + .config = bcm2835_pwm_config, + .enable = bcm2835_pwm_enable, + .disable = bcm2835_pwm_disable, + .set_polarity = bcm2835_set_polarity, + .owner = THIS_MODULE, +}; + +static int bcm2835_pwm_probe(struct platform_device *pdev) +{ + struct bcm2835_pwm *pc; + struct resource *res; + int ret; + + pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL); + if (!pc) + return -ENOMEM; + + pc->dev = &pdev->dev; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + pc->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(pc->base)) + return PTR_ERR(pc->base); + + pc->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(pc->clk)) { + dev_err(&pdev->dev, "clock not found: %ld\n", PTR_ERR(pc->clk)); + return PTR_ERR(pc->clk); + } + + ret = clk_prepare_enable(pc->clk); + if (ret) + return ret; + + pc->scaler = NSEC_PER_SEC / clk_get_rate(pc->clk); + + pc->chip.dev = &pdev->dev; + pc->chip.ops = &bcm2835_pwm_ops; + pc->chip.npwm = 2; + + platform_set_drvdata(pdev, pc); + + ret = pwmchip_add(&pc->chip); + if (ret < 0) + goto add_fail; + + return 0; + +add_fail: + clk_disable_unprepare(pc->clk); + return ret; +} + +static int bcm2835_pwm_remove(struct platform_device *pdev) +{ + struct bcm2835_pwm *pc = platform_get_drvdata(pdev); + + clk_disable_unprepare(pc->clk); + + return pwmchip_remove(&pc->chip); +} + +static const struct of_device_id bcm2835_pwm_of_match[] = { + { .compatible = "brcm,bcm2835-pwm", }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, bcm2835_pwm_of_match); + +static struct platform_driver bcm2835_pwm_driver = { + .driver = { + .name = "bcm2835-pwm", + .of_match_table = bcm2835_pwm_of_match, + }, + .probe = bcm2835_pwm_probe, + .remove = bcm2835_pwm_remove, +}; +module_platform_driver(bcm2835_pwm_driver); + +MODULE_AUTHOR("Bart Tanghe Date: Tue, 7 Oct 2014 15:38:14 +0200 Subject: pwm: add support for atmel-hlcdc-pwm device The HLCDC IP available in some Atmel SoCs (i.e. at91sam9x5, at91sam9n12 or sama5d3 families for instance) provides a PWM device. This driver add support for a PWM chip exposing a single PWM device (which will most likely be used to drive a backlight device). Signed-off-by: Boris Brezillon Tested-by: Anthony Harivel Tested-by: Ludovic Desroches Acked-by: Thierry Reding Acked-by: Nicolas Ferre Signed-off-by: Thierry Reding diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig index ddabe39..847a57d 100644 --- a/drivers/pwm/Kconfig +++ b/drivers/pwm/Kconfig @@ -50,6 +50,17 @@ config PWM_ATMEL To compile this driver as a module, choose M here: the module will be called pwm-atmel. +config PWM_ATMEL_HLCDC_PWM + tristate "Atmel HLCDC PWM support" + depends on MFD_ATMEL_HLCDC + help + Generic PWM framework driver for the PWM output of the HLCDC + (Atmel High-end LCD Controller). This PWM output is mainly used + to control the LCD backlight. + + To compile this driver as a module, choose M here: the module + will be called pwm-atmel-hlcdc. + config PWM_ATMEL_TCB tristate "Atmel TC Block PWM support" depends on ATMEL_TCLIB && OF diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile index 88be33b..65259ac 100644 --- a/drivers/pwm/Makefile +++ b/drivers/pwm/Makefile @@ -2,6 +2,7 @@ obj-$(CONFIG_PWM) += core.o obj-$(CONFIG_PWM_SYSFS) += sysfs.o obj-$(CONFIG_PWM_AB8500) += pwm-ab8500.o obj-$(CONFIG_PWM_ATMEL) += pwm-atmel.o +obj-$(CONFIG_PWM_ATMEL_HLCDC_PWM) += pwm-atmel-hlcdc.o obj-$(CONFIG_PWM_ATMEL_TCB) += pwm-atmel-tcb.o obj-$(CONFIG_PWM_BCM_KONA) += pwm-bcm-kona.o obj-$(CONFIG_PWM_BCM2835) += pwm-bcm2835.o diff --git a/drivers/pwm/pwm-atmel-hlcdc.c b/drivers/pwm/pwm-atmel-hlcdc.c new file mode 100644 index 0000000..eaf8b12 --- /dev/null +++ b/drivers/pwm/pwm-atmel-hlcdc.c @@ -0,0 +1,259 @@ +/* + * Copyright (C) 2014 Free Electrons + * Copyright (C) 2014 Atmel + * + * Author: Boris BREZILLON + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program. If not, see . + */ + +#include +#include +#include +#include +#include +#include +#include + +#define ATMEL_HLCDC_PWMCVAL_MASK GENMASK(15, 8) +#define ATMEL_HLCDC_PWMCVAL(x) (((x) << 8) & ATMEL_HLCDC_PWMCVAL_MASK) +#define ATMEL_HLCDC_PWMPOL BIT(4) +#define ATMEL_HLCDC_PWMPS_MASK GENMASK(2, 0) +#define ATMEL_HLCDC_PWMPS_MAX 0x6 +#define ATMEL_HLCDC_PWMPS(x) ((x) & ATMEL_HLCDC_PWMPS_MASK) + +struct atmel_hlcdc_pwm { + struct pwm_chip chip; + struct atmel_hlcdc *hlcdc; + struct clk *cur_clk; +}; + +static inline struct atmel_hlcdc_pwm *to_atmel_hlcdc_pwm(struct pwm_chip *chip) +{ + return container_of(chip, struct atmel_hlcdc_pwm, chip); +} + +static int atmel_hlcdc_pwm_config(struct pwm_chip *c, + struct pwm_device *pwm, + int duty_ns, int period_ns) +{ + struct atmel_hlcdc_pwm *chip = to_atmel_hlcdc_pwm(c); + struct atmel_hlcdc *hlcdc = chip->hlcdc; + struct clk *new_clk = hlcdc->slow_clk; + u64 pwmcval = duty_ns * 256; + unsigned long clk_freq; + u64 clk_period_ns; + u32 pwmcfg; + int pres; + + clk_freq = clk_get_rate(new_clk); + clk_period_ns = (u64)NSEC_PER_SEC * 256; + do_div(clk_period_ns, clk_freq); + + if (clk_period_ns > period_ns) { + new_clk = hlcdc->sys_clk; + clk_freq = clk_get_rate(new_clk); + clk_period_ns = (u64)NSEC_PER_SEC * 256; + do_div(clk_period_ns, clk_freq); + } + + for (pres = 0; pres <= ATMEL_HLCDC_PWMPS_MAX; pres++) + if ((clk_period_ns << pres) >= period_ns) + break; + + if (pres > ATMEL_HLCDC_PWMPS_MAX) + return -EINVAL; + + pwmcfg = ATMEL_HLCDC_PWMPS(pres); + + if (new_clk != chip->cur_clk) { + u32 gencfg = 0; + int ret; + + ret = clk_prepare_enable(new_clk); + if (ret) + return ret; + + clk_disable_unprepare(chip->cur_clk); + chip->cur_clk = new_clk; + + if (new_clk == hlcdc->sys_clk) + gencfg = ATMEL_HLCDC_CLKPWMSEL; + + ret = regmap_update_bits(hlcdc->regmap, ATMEL_HLCDC_CFG(0), + ATMEL_HLCDC_CLKPWMSEL, gencfg); + if (ret) + return ret; + } + + do_div(pwmcval, period_ns); + + /* + * The PWM duty cycle is configurable from 0/256 to 255/256 of the + * period cycle. Hence we can't set a duty cycle occupying the + * whole period cycle if we're asked to. + * Set it to 255 if pwmcval is greater than 256. + */ + if (pwmcval > 255) + pwmcval = 255; + + pwmcfg |= ATMEL_HLCDC_PWMCVAL(pwmcval); + + return regmap_update_bits(hlcdc->regmap, ATMEL_HLCDC_CFG(6), + ATMEL_HLCDC_PWMCVAL_MASK | + ATMEL_HLCDC_PWMPS_MASK, + pwmcfg); +} + +static int atmel_hlcdc_pwm_set_polarity(struct pwm_chip *c, + struct pwm_device *pwm, + enum pwm_polarity polarity) +{ + struct atmel_hlcdc_pwm *chip = to_atmel_hlcdc_pwm(c); + struct atmel_hlcdc *hlcdc = chip->hlcdc; + u32 cfg = 0; + + if (polarity == PWM_POLARITY_NORMAL) + cfg = ATMEL_HLCDC_PWMPOL; + + return regmap_update_bits(hlcdc->regmap, ATMEL_HLCDC_CFG(6), + ATMEL_HLCDC_PWMPOL, cfg); +} + +static int atmel_hlcdc_pwm_enable(struct pwm_chip *c, struct pwm_device *pwm) +{ + struct atmel_hlcdc_pwm *chip = to_atmel_hlcdc_pwm(c); + struct atmel_hlcdc *hlcdc = chip->hlcdc; + u32 status; + int ret; + + ret = regmap_write(hlcdc->regmap, ATMEL_HLCDC_EN, ATMEL_HLCDC_PWM); + if (ret) + return ret; + + while (true) { + ret = regmap_read(hlcdc->regmap, ATMEL_HLCDC_SR, &status); + if (ret) + return ret; + + if ((status & ATMEL_HLCDC_PWM) != 0) + break; + + usleep_range(1, 10); + } + + return 0; +} + +static void atmel_hlcdc_pwm_disable(struct pwm_chip *c, + struct pwm_device *pwm) +{ + struct atmel_hlcdc_pwm *chip = to_atmel_hlcdc_pwm(c); + struct atmel_hlcdc *hlcdc = chip->hlcdc; + u32 status; + int ret; + + ret = regmap_write(hlcdc->regmap, ATMEL_HLCDC_DIS, ATMEL_HLCDC_PWM); + if (ret) + return; + + while (true) { + ret = regmap_read(hlcdc->regmap, ATMEL_HLCDC_SR, &status); + if (ret) + return; + + if ((status & ATMEL_HLCDC_PWM) == 0) + break; + + usleep_range(1, 10); + } +} + +static const struct pwm_ops atmel_hlcdc_pwm_ops = { + .config = atmel_hlcdc_pwm_config, + .set_polarity = atmel_hlcdc_pwm_set_polarity, + .enable = atmel_hlcdc_pwm_enable, + .disable = atmel_hlcdc_pwm_disable, + .owner = THIS_MODULE, +}; + +static int atmel_hlcdc_pwm_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct atmel_hlcdc_pwm *chip; + struct atmel_hlcdc *hlcdc; + int ret; + + hlcdc = dev_get_drvdata(dev->parent); + + chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL); + if (!chip) + return -ENOMEM; + + ret = clk_prepare_enable(hlcdc->periph_clk); + if (ret) + return ret; + + chip->hlcdc = hlcdc; + chip->chip.ops = &atmel_hlcdc_pwm_ops; + chip->chip.dev = dev; + chip->chip.base = -1; + chip->chip.npwm = 1; + chip->chip.of_xlate = of_pwm_xlate_with_flags; + chip->chip.of_pwm_n_cells = 3; + chip->chip.can_sleep = 1; + + ret = pwmchip_add(&chip->chip); + if (ret) { + clk_disable_unprepare(hlcdc->periph_clk); + return ret; + } + + platform_set_drvdata(pdev, chip); + + return 0; +} + +static int atmel_hlcdc_pwm_remove(struct platform_device *pdev) +{ + struct atmel_hlcdc_pwm *chip = platform_get_drvdata(pdev); + int ret; + + ret = pwmchip_remove(&chip->chip); + if (ret) + return ret; + + clk_disable_unprepare(chip->hlcdc->periph_clk); + + return 0; +} + +static const struct of_device_id atmel_hlcdc_pwm_dt_ids[] = { + { .compatible = "atmel,hlcdc-pwm" }, + { /* sentinel */ }, +}; + +static struct platform_driver atmel_hlcdc_pwm_driver = { + .driver = { + .name = "atmel-hlcdc-pwm", + .of_match_table = atmel_hlcdc_pwm_dt_ids, + }, + .probe = atmel_hlcdc_pwm_probe, + .remove = atmel_hlcdc_pwm_remove, +}; +module_platform_driver(atmel_hlcdc_pwm_driver); + +MODULE_ALIAS("platform:atmel-hlcdc-pwm"); +MODULE_AUTHOR("Boris Brezillon "); +MODULE_DESCRIPTION("Atmel HLCDC PWM driver"); +MODULE_LICENSE("GPL v2"); -- cgit v0.10.2 From 2899e12fc9864db600b2fe9707ebb97203fe4c00 Mon Sep 17 00:00:00 2001 From: Boris Brezillon Date: Tue, 7 Oct 2014 15:38:15 +0200 Subject: pwm: add DT bindings documentation for atmel-hlcdc-pwm driver The HLCDC IP available in some Atmel SoCs (i.e. at91sam9x5, at91sam9n12 or sama5d3 families for instance) provides a PWM device. The DT bindings used for this PWM device is following the default 3 cells bindings described in Documentation/devicetree/bindings/pwm/pwm.txt. Signed-off-by: Boris Brezillon Acked-by: Thierry Reding Acked-by: Nicolas Ferre Signed-off-by: Thierry Reding diff --git a/Documentation/devicetree/bindings/pwm/atmel-hlcdc-pwm.txt b/Documentation/devicetree/bindings/pwm/atmel-hlcdc-pwm.txt new file mode 100644 index 0000000..cfda0d5 --- /dev/null +++ b/Documentation/devicetree/bindings/pwm/atmel-hlcdc-pwm.txt @@ -0,0 +1,29 @@ +Device-Tree bindings for Atmel's HLCDC (High-end LCD Controller) PWM driver + +The Atmel HLCDC PWM is subdevice of the HLCDC MFD device. +See ../mfd/atmel-hlcdc.txt for more details. + +Required properties: + - compatible: value should be one of the following: + "atmel,hlcdc-pwm" + - pinctr-names: the pin control state names. Should contain "default". + - pinctrl-0: should contain the pinctrl states described by pinctrl + default. + - #pwm-cells: should be set to 3. This PWM chip use the default 3 cells + bindings defined in pwm.txt in this directory. + +Example: + + hlcdc: hlcdc@f0030000 { + compatible = "atmel,sama5d3-hlcdc"; + reg = <0xf0030000 0x2000>; + clocks = <&lcdc_clk>, <&lcdck>, <&clk32k>; + clock-names = "periph_clk","sys_clk", "slow_clk"; + + hlcdc_pwm: hlcdc-pwm { + compatible = "atmel,hlcdc-pwm"; + pinctrl-names = "default"; + pinctrl-0 = <&pinctrl_lcd_pwm>; + #pwm-cells = <3>; + }; + }; -- cgit v0.10.2 From 06e4cb6b1d5c9dba007b1f7a039384b2fc1a8827 Mon Sep 17 00:00:00 2001 From: Abhilash Kesavan Date: Fri, 31 Oct 2014 18:08:46 +0530 Subject: pwm: samsung: Allow Samsung PWM driver to be enabled on Exynos7 To re-use the existing PWM driver for 64-bit ARM based Exynos7 SoC, make the driver depend on ARCH_EXYNOS along with PLAT_SAMSUNG. Signed-off-by: Abhilash Kesavan Signed-off-by: Thierry Reding diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig index 847a57d..a3ecf58 100644 --- a/drivers/pwm/Kconfig +++ b/drivers/pwm/Kconfig @@ -255,7 +255,7 @@ config PWM_ROCKCHIP config PWM_SAMSUNG tristate "Samsung PWM support" - depends on PLAT_SAMSUNG + depends on PLAT_SAMSUNG || ARCH_EXYNOS help Generic PWM framework driver for Samsung. -- cgit v0.10.2 From 8e6e76510287d1a08c7c36e8e076b1314f59d9c4 Mon Sep 17 00:00:00 2001 From: Xiubo Li Date: Wed, 15 Oct 2014 13:21:33 +0800 Subject: pwm: ftm: Correctly track usage count No matter how many times the FTM PWM is enabled, the use_count will always be one. Signed-off-by: Xiubo Li Signed-off-by: Thierry Reding diff --git a/drivers/pwm/pwm-fsl-ftm.c b/drivers/pwm/pwm-fsl-ftm.c index 0f2cc7e..1150598 100644 --- a/drivers/pwm/pwm-fsl-ftm.c +++ b/drivers/pwm/pwm-fsl-ftm.c @@ -299,7 +299,7 @@ static int fsl_counter_clock_enable(struct fsl_pwm_chip *fpc) { int ret; - if (fpc->use_count != 0) + if (fpc->use_count++ != 0) return 0; /* select counter clock source */ @@ -316,8 +316,6 @@ static int fsl_counter_clock_enable(struct fsl_pwm_chip *fpc) return ret; } - fpc->use_count++; - return 0; } -- cgit v0.10.2 From 49599cf6bb8098ecde64f2bda3337b5fcf6323c5 Mon Sep 17 00:00:00 2001 From: Xiubo Li Date: Wed, 15 Oct 2014 13:21:34 +0800 Subject: pwm: ftm: Add regmap rbtree type cache support This patch is to prepare for adding PM support for FTM PWM driver using callback function suspend and resume in .driver.pm of platform_driver. Signed-off-by: Xiubo Li Signed-off-by: Thierry Reding diff --git a/drivers/pwm/pwm-fsl-ftm.c b/drivers/pwm/pwm-fsl-ftm.c index 1150598..9bfbea5 100644 --- a/drivers/pwm/pwm-fsl-ftm.c +++ b/drivers/pwm/pwm-fsl-ftm.c @@ -397,12 +397,23 @@ static int fsl_pwm_init(struct fsl_pwm_chip *fpc) return 0; } +static bool fsl_pwm_volatile_reg(struct device *dev, unsigned int reg) +{ + switch (reg) { + case FTM_CNT: + return true; + } + return false; +} + static const struct regmap_config fsl_pwm_regmap_config = { .reg_bits = 32, .reg_stride = 4, .val_bits = 32, .max_register = FTM_PWMLOAD, + .volatile_reg = fsl_pwm_volatile_reg, + .cache_type = REGCACHE_RBTREE, }; static int fsl_pwm_probe(struct platform_device *pdev) -- cgit v0.10.2 From 97d0b42e39a73c7e0683927ee4b3775c7411b7bf Mon Sep 17 00:00:00 2001 From: Xiubo Li Date: Wed, 15 Oct 2014 13:21:35 +0800 Subject: pwm: ftm: Add Power Management support for FTM PWM Add PM support for FTM PWM driver using callback function suspend and resume in .driver.pm of platform_driver. Signed-off-by: Xiubo Li Signed-off-by: Thierry Reding diff --git a/drivers/pwm/pwm-fsl-ftm.c b/drivers/pwm/pwm-fsl-ftm.c index 9bfbea5..f9dfc8b 100644 --- a/drivers/pwm/pwm-fsl-ftm.c +++ b/drivers/pwm/pwm-fsl-ftm.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #include #include @@ -436,7 +437,7 @@ static int fsl_pwm_probe(struct platform_device *pdev) if (IS_ERR(base)) return PTR_ERR(base); - fpc->regmap = devm_regmap_init_mmio_clk(&pdev->dev, NULL, base, + fpc->regmap = devm_regmap_init_mmio_clk(&pdev->dev, "ftm_sys", base, &fsl_pwm_regmap_config); if (IS_ERR(fpc->regmap)) { dev_err(&pdev->dev, "regmap init failed\n"); @@ -487,6 +488,51 @@ static int fsl_pwm_remove(struct platform_device *pdev) return pwmchip_remove(&fpc->chip); } +#ifdef CONFIG_PM_SLEEP +static int fsl_pwm_suspend(struct device *dev) +{ + struct fsl_pwm_chip *fpc = dev_get_drvdata(dev); + u32 val; + + regcache_cache_only(fpc->regmap, true); + regcache_mark_dirty(fpc->regmap); + + /* read from cache */ + regmap_read(fpc->regmap, FTM_OUTMASK, &val); + if ((val & 0xFF) != 0xFF) { + clk_disable_unprepare(fpc->clk[FSL_PWM_CLK_CNTEN]); + clk_disable_unprepare(fpc->clk[fpc->cnt_select]); + clk_disable_unprepare(fpc->clk[FSL_PWM_CLK_SYS]); + } + + return 0; +} + +static int fsl_pwm_resume(struct device *dev) +{ + struct fsl_pwm_chip *fpc = dev_get_drvdata(dev); + u32 val; + + /* read from cache */ + regmap_read(fpc->regmap, FTM_OUTMASK, &val); + if ((val & 0xFF) != 0xFF) { + clk_prepare_enable(fpc->clk[FSL_PWM_CLK_SYS]); + clk_prepare_enable(fpc->clk[fpc->cnt_select]); + clk_prepare_enable(fpc->clk[FSL_PWM_CLK_CNTEN]); + } + + /* restore all registers from cache */ + regcache_cache_only(fpc->regmap, false); + regcache_sync(fpc->regmap); + + return 0; +} +#endif + +static const struct dev_pm_ops fsl_pwm_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(fsl_pwm_suspend, fsl_pwm_resume) +}; + static const struct of_device_id fsl_pwm_dt_ids[] = { { .compatible = "fsl,vf610-ftm-pwm", }, { /* sentinel */ } @@ -497,6 +543,7 @@ static struct platform_driver fsl_pwm_driver = { .driver = { .name = "fsl-ftm-pwm", .of_match_table = fsl_pwm_dt_ids, + .pm = &fsl_pwm_pm_ops, }, .probe = fsl_pwm_probe, .remove = fsl_pwm_remove, -- cgit v0.10.2 From 39e046f2c1dd0742976d7ee6e464744cf2122f41 Mon Sep 17 00:00:00 2001 From: Boris BREZILLON Date: Wed, 19 Nov 2014 15:33:09 +0100 Subject: pwm: atmel-hlcdc: add at91sam9x5 and sama5d3 errata handling at91sam9x5 has an errata forbidding the use of slow clk as a clk source and sama5d3 SoCs has another errata forbidding the use of div1 prescaler. Take both of these erratas into account. Signed-off-by: Boris Brezillon Acked-by: Nicolas Ferre Signed-off-by: Thierry Reding diff --git a/drivers/pwm/pwm-atmel-hlcdc.c b/drivers/pwm/pwm-atmel-hlcdc.c index eaf8b12..e7a785f 100644 --- a/drivers/pwm/pwm-atmel-hlcdc.c +++ b/drivers/pwm/pwm-atmel-hlcdc.c @@ -32,10 +32,16 @@ #define ATMEL_HLCDC_PWMPS_MAX 0x6 #define ATMEL_HLCDC_PWMPS(x) ((x) & ATMEL_HLCDC_PWMPS_MASK) +struct atmel_hlcdc_pwm_errata { + bool slow_clk_erratum; + bool div1_clk_erratum; +}; + struct atmel_hlcdc_pwm { struct pwm_chip chip; struct atmel_hlcdc *hlcdc; struct clk *cur_clk; + const struct atmel_hlcdc_pwm_errata *errata; }; static inline struct atmel_hlcdc_pwm *to_atmel_hlcdc_pwm(struct pwm_chip *chip) @@ -56,20 +62,29 @@ static int atmel_hlcdc_pwm_config(struct pwm_chip *c, u32 pwmcfg; int pres; - clk_freq = clk_get_rate(new_clk); - clk_period_ns = (u64)NSEC_PER_SEC * 256; - do_div(clk_period_ns, clk_freq); + if (!chip->errata || !chip->errata->slow_clk_erratum) { + clk_freq = clk_get_rate(new_clk); + clk_period_ns = (u64)NSEC_PER_SEC * 256; + do_div(clk_period_ns, clk_freq); + } - if (clk_period_ns > period_ns) { + /* Errata: cannot use slow clk on some IP revisions */ + if ((chip->errata && chip->errata->slow_clk_erratum) || + clk_period_ns > period_ns) { new_clk = hlcdc->sys_clk; clk_freq = clk_get_rate(new_clk); clk_period_ns = (u64)NSEC_PER_SEC * 256; do_div(clk_period_ns, clk_freq); } - for (pres = 0; pres <= ATMEL_HLCDC_PWMPS_MAX; pres++) + for (pres = 0; pres <= ATMEL_HLCDC_PWMPS_MAX; pres++) { + /* Errata: cannot divide by 1 on some IP revisions */ + if (!pres && chip->errata && chip->errata->div1_clk_erratum) + continue; + if ((clk_period_ns << pres) >= period_ns) break; + } if (pres > ATMEL_HLCDC_PWMPS_MAX) return -EINVAL; @@ -187,8 +202,29 @@ static const struct pwm_ops atmel_hlcdc_pwm_ops = { .owner = THIS_MODULE, }; +static const struct atmel_hlcdc_pwm_errata atmel_hlcdc_pwm_at91sam9x5_errata = { + .slow_clk_erratum = true, +}; + +static const struct atmel_hlcdc_pwm_errata atmel_hlcdc_pwm_sama5d3_errata = { + .div1_clk_erratum = true, +}; + +static const struct of_device_id atmel_hlcdc_dt_ids[] = { + { + .compatible = "atmel,at91sam9x5-hlcdc", + .data = &atmel_hlcdc_pwm_at91sam9x5_errata, + }, + { + .compatible = "atmel,sama5d3-hlcdc", + .data = &atmel_hlcdc_pwm_sama5d3_errata, + }, + { /* sentinel */ }, +}; + static int atmel_hlcdc_pwm_probe(struct platform_device *pdev) { + const struct of_device_id *match; struct device *dev = &pdev->dev; struct atmel_hlcdc_pwm *chip; struct atmel_hlcdc *hlcdc; @@ -204,6 +240,10 @@ static int atmel_hlcdc_pwm_probe(struct platform_device *pdev) if (ret) return ret; + match = of_match_node(atmel_hlcdc_dt_ids, dev->parent->of_node); + if (match) + chip->errata = match->data; + chip->hlcdc = hlcdc; chip->chip.ops = &atmel_hlcdc_pwm_ops; chip->chip.dev = dev; -- cgit v0.10.2