diff options
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/iio/trigger/Kconfig | 9 | ||||
-rw-r--r-- | drivers/iio/trigger/Makefile | 1 | ||||
-rw-r--r-- | drivers/iio/trigger/stm32-timer-trigger.c | 342 | ||||
-rw-r--r-- | drivers/mfd/Kconfig | 11 | ||||
-rw-r--r-- | drivers/mfd/Makefile | 2 | ||||
-rw-r--r-- | drivers/mfd/stm32-timers.c | 80 | ||||
-rw-r--r-- | drivers/pwm/Kconfig | 9 | ||||
-rw-r--r-- | drivers/pwm/Makefile | 1 | ||||
-rw-r--r-- | drivers/pwm/pwm-stm32.c | 397 |
9 files changed, 852 insertions, 0 deletions
diff --git a/drivers/iio/trigger/Kconfig b/drivers/iio/trigger/Kconfig index 809b2e7d58fa..e4d4e63434db 100644 --- a/drivers/iio/trigger/Kconfig +++ b/drivers/iio/trigger/Kconfig @@ -24,6 +24,15 @@ config IIO_INTERRUPT_TRIGGER To compile this driver as a module, choose M here: the module will be called iio-trig-interrupt. +config IIO_STM32_TIMER_TRIGGER + tristate "STM32 Timer Trigger" + depends on (ARCH_STM32 && OF && MFD_STM32_TIMERS) || COMPILE_TEST + help + Select this option to enable STM32 Timer Trigger + + To compile this driver as a module, choose M here: the + module will be called stm32-timer-trigger. + config IIO_TIGHTLOOP_TRIGGER tristate "A kthread based hammering loop trigger" depends on IIO_SW_TRIGGER diff --git a/drivers/iio/trigger/Makefile b/drivers/iio/trigger/Makefile index aab4dc23303d..5c4ecd380653 100644 --- a/drivers/iio/trigger/Makefile +++ b/drivers/iio/trigger/Makefile @@ -6,5 +6,6 @@ obj-$(CONFIG_IIO_HRTIMER_TRIGGER) += iio-trig-hrtimer.o obj-$(CONFIG_IIO_INTERRUPT_TRIGGER) += iio-trig-interrupt.o +obj-$(CONFIG_IIO_STM32_TIMER_TRIGGER) += stm32-timer-trigger.o obj-$(CONFIG_IIO_SYSFS_TRIGGER) += iio-trig-sysfs.o obj-$(CONFIG_IIO_TIGHTLOOP_TRIGGER) += iio-trig-loop.o diff --git a/drivers/iio/trigger/stm32-timer-trigger.c b/drivers/iio/trigger/stm32-timer-trigger.c new file mode 100644 index 000000000000..994b96d19750 --- /dev/null +++ b/drivers/iio/trigger/stm32-timer-trigger.c @@ -0,0 +1,342 @@ +/* + * Copyright (C) STMicroelectronics 2016 + * + * Author: Benjamin Gaignard <benjamin.gaignard@st.com> + * + * License terms: GNU General Public License (GPL), version 2 + */ + +#include <linux/iio/iio.h> +#include <linux/iio/sysfs.h> +#include <linux/iio/timer/stm32-timer-trigger.h> +#include <linux/iio/trigger.h> +#include <linux/mfd/stm32-timers.h> +#include <linux/module.h> +#include <linux/platform_device.h> + +#define MAX_TRIGGERS 6 + +/* List the triggers created by each timer */ +static const void *triggers_table[][MAX_TRIGGERS] = { + { TIM1_TRGO, TIM1_CH1, TIM1_CH2, TIM1_CH3, TIM1_CH4,}, + { TIM2_TRGO, TIM2_CH1, TIM2_CH2, TIM2_CH3, TIM2_CH4,}, + { TIM3_TRGO, TIM3_CH1, TIM3_CH2, TIM3_CH3, TIM3_CH4,}, + { TIM4_TRGO, TIM4_CH1, TIM4_CH2, TIM4_CH3, TIM4_CH4,}, + { TIM5_TRGO, TIM5_CH1, TIM5_CH2, TIM5_CH3, TIM5_CH4,}, + { TIM6_TRGO,}, + { TIM7_TRGO,}, + { TIM8_TRGO, TIM8_CH1, TIM8_CH2, TIM8_CH3, TIM8_CH4,}, + { TIM9_TRGO, TIM9_CH1, TIM9_CH2,}, + { }, /* timer 10 */ + { }, /* timer 11 */ + { TIM12_TRGO, TIM12_CH1, TIM12_CH2,}, +}; + +struct stm32_timer_trigger { + struct device *dev; + struct regmap *regmap; + struct clk *clk; + u32 max_arr; + const void *triggers; +}; + +static int stm32_timer_start(struct stm32_timer_trigger *priv, + unsigned int frequency) +{ + unsigned long long prd, div; + int prescaler = 0; + u32 ccer, cr1; + + /* Period and prescaler values depends of clock rate */ + div = (unsigned long long)clk_get_rate(priv->clk); + + do_div(div, frequency); + + prd = div; + + /* + * Increase prescaler value until we get a result that fit + * with auto reload register maximum value. + */ + while (div > priv->max_arr) { + prescaler++; + div = prd; + do_div(div, (prescaler + 1)); + } + prd = div; + + if (prescaler > MAX_TIM_PSC) { + dev_err(priv->dev, "prescaler exceeds the maximum value\n"); + return -EINVAL; + } + + /* Check if nobody else use the timer */ + regmap_read(priv->regmap, TIM_CCER, &ccer); + if (ccer & TIM_CCER_CCXE) + return -EBUSY; + + regmap_read(priv->regmap, TIM_CR1, &cr1); + if (!(cr1 & TIM_CR1_CEN)) + clk_enable(priv->clk); + + regmap_write(priv->regmap, TIM_PSC, prescaler); + regmap_write(priv->regmap, TIM_ARR, prd - 1); + regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_ARPE, TIM_CR1_ARPE); + + /* Force master mode to update mode */ + regmap_update_bits(priv->regmap, TIM_CR2, TIM_CR2_MMS, 0x20); + + /* Make sure that registers are updated */ + regmap_update_bits(priv->regmap, TIM_EGR, TIM_EGR_UG, TIM_EGR_UG); + + /* Enable controller */ + regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, TIM_CR1_CEN); + + return 0; +} + +static void stm32_timer_stop(struct stm32_timer_trigger *priv) +{ + u32 ccer, cr1; + + regmap_read(priv->regmap, TIM_CCER, &ccer); + if (ccer & TIM_CCER_CCXE) + return; + + regmap_read(priv->regmap, TIM_CR1, &cr1); + if (cr1 & TIM_CR1_CEN) + clk_disable(priv->clk); + + /* Stop timer */ + regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, 0); + regmap_write(priv->regmap, TIM_PSC, 0); + regmap_write(priv->regmap, TIM_ARR, 0); + + /* Make sure that registers are updated */ + regmap_update_bits(priv->regmap, TIM_EGR, TIM_EGR_UG, TIM_EGR_UG); +} + +static ssize_t stm32_tt_store_frequency(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t len) +{ + struct iio_trigger *trig = to_iio_trigger(dev); + struct stm32_timer_trigger *priv = iio_trigger_get_drvdata(trig); + unsigned int freq; + int ret; + + ret = kstrtouint(buf, 10, &freq); + if (ret) + return ret; + + if (freq == 0) { + stm32_timer_stop(priv); + } else { + ret = stm32_timer_start(priv, freq); + if (ret) + return ret; + } + + return len; +} + +static ssize_t stm32_tt_read_frequency(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct iio_trigger *trig = to_iio_trigger(dev); + struct stm32_timer_trigger *priv = iio_trigger_get_drvdata(trig); + u32 psc, arr, cr1; + unsigned long long freq = 0; + + regmap_read(priv->regmap, TIM_CR1, &cr1); + regmap_read(priv->regmap, TIM_PSC, &psc); + regmap_read(priv->regmap, TIM_ARR, &arr); + + if (psc && arr && (cr1 & TIM_CR1_CEN)) { + freq = (unsigned long long)clk_get_rate(priv->clk); + do_div(freq, psc); + do_div(freq, arr); + } + + return sprintf(buf, "%d\n", (unsigned int)freq); +} + +static IIO_DEV_ATTR_SAMP_FREQ(0660, + stm32_tt_read_frequency, + stm32_tt_store_frequency); + +static char *master_mode_table[] = { + "reset", + "enable", + "update", + "compare_pulse", + "OC1REF", + "OC2REF", + "OC3REF", + "OC4REF" +}; + +static ssize_t stm32_tt_show_master_mode(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *indio_dev = dev_to_iio_dev(dev); + struct stm32_timer_trigger *priv = iio_priv(indio_dev); + u32 cr2; + + regmap_read(priv->regmap, TIM_CR2, &cr2); + cr2 = (cr2 & TIM_CR2_MMS) >> TIM_CR2_MMS_SHIFT; + + return snprintf(buf, PAGE_SIZE, "%s\n", master_mode_table[cr2]); +} + +static ssize_t stm32_tt_store_master_mode(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t len) +{ + struct iio_dev *indio_dev = dev_to_iio_dev(dev); + struct stm32_timer_trigger *priv = iio_priv(indio_dev); + int i; + + for (i = 0; i < ARRAY_SIZE(master_mode_table); i++) { + if (!strncmp(master_mode_table[i], buf, + strlen(master_mode_table[i]))) { + regmap_update_bits(priv->regmap, TIM_CR2, + TIM_CR2_MMS, i << TIM_CR2_MMS_SHIFT); + /* Make sure that registers are updated */ + regmap_update_bits(priv->regmap, TIM_EGR, + TIM_EGR_UG, TIM_EGR_UG); + return len; + } + } + + return -EINVAL; +} + +static IIO_CONST_ATTR(master_mode_available, + "reset enable update compare_pulse OC1REF OC2REF OC3REF OC4REF"); + +static IIO_DEVICE_ATTR(master_mode, 0660, + stm32_tt_show_master_mode, + stm32_tt_store_master_mode, + 0); + +static struct attribute *stm32_trigger_attrs[] = { + &iio_dev_attr_sampling_frequency.dev_attr.attr, + &iio_dev_attr_master_mode.dev_attr.attr, + &iio_const_attr_master_mode_available.dev_attr.attr, + NULL, +}; + +static const struct attribute_group stm32_trigger_attr_group = { + .attrs = stm32_trigger_attrs, +}; + +static const struct attribute_group *stm32_trigger_attr_groups[] = { + &stm32_trigger_attr_group, + NULL, +}; + +static const struct iio_trigger_ops timer_trigger_ops = { + .owner = THIS_MODULE, +}; + +static int stm32_setup_iio_triggers(struct stm32_timer_trigger *priv) +{ + int ret; + const char * const *cur = priv->triggers; + + while (cur && *cur) { + struct iio_trigger *trig; + + trig = devm_iio_trigger_alloc(priv->dev, "%s", *cur); + if (!trig) + return -ENOMEM; + + trig->dev.parent = priv->dev->parent; + trig->ops = &timer_trigger_ops; + + /* + * sampling frequency and master mode attributes + * should only be available on trgo trigger which + * is always the first in the list. + */ + if (cur == priv->triggers) + trig->dev.groups = stm32_trigger_attr_groups; + + iio_trigger_set_drvdata(trig, priv); + + ret = devm_iio_trigger_register(priv->dev, trig); + if (ret) + return ret; + cur++; + } + + return 0; +} + +/** + * is_stm32_timer_trigger + * @trig: trigger to be checked + * + * return true if the trigger is a valid stm32 iio timer trigger + * either return false + */ +bool is_stm32_timer_trigger(struct iio_trigger *trig) +{ + return (trig->ops == &timer_trigger_ops); +} +EXPORT_SYMBOL(is_stm32_timer_trigger); + +static int stm32_timer_trigger_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct stm32_timer_trigger *priv; + struct stm32_timers *ddata = dev_get_drvdata(pdev->dev.parent); + unsigned int index; + int ret; + + if (of_property_read_u32(dev->of_node, "reg", &index)) + return -EINVAL; + + if (index >= ARRAY_SIZE(triggers_table)) + return -EINVAL; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + + if (!priv) + return -ENOMEM; + + priv->dev = dev; + priv->regmap = ddata->regmap; + priv->clk = ddata->clk; + priv->max_arr = ddata->max_arr; + priv->triggers = triggers_table[index]; + + ret = stm32_setup_iio_triggers(priv); + if (ret) + return ret; + + platform_set_drvdata(pdev, priv); + + return 0; +} + +static const struct of_device_id stm32_trig_of_match[] = { + { .compatible = "st,stm32-timer-trigger", }, + { /* end node */ }, +}; +MODULE_DEVICE_TABLE(of, stm32_trig_of_match); + +static struct platform_driver stm32_timer_trigger_driver = { + .probe = stm32_timer_trigger_probe, + .driver = { + .name = "stm32-timer-trigger", + .of_match_table = stm32_trig_of_match, + }, +}; +module_platform_driver(stm32_timer_trigger_driver); + +MODULE_ALIAS("platform: stm32-timer-trigger"); +MODULE_DESCRIPTION("STMicroelectronics STM32 Timer Trigger driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig index 4ce3b6f11830..d0c14b88b24e 100644 --- a/drivers/mfd/Kconfig +++ b/drivers/mfd/Kconfig @@ -1621,6 +1621,17 @@ config MFD_STW481X in various ST Microelectronics and ST-Ericsson embedded Nomadik series. +config MFD_STM32_TIMERS + tristate "Support for STM32 Timers" + depends on (ARCH_STM32 && OF) || COMPILE_TEST + select MFD_CORE + select REGMAP + select REGMAP_MMIO + help + Select this option to enable STM32 timers driver used + for PWM and IIO Timer. This driver allow to share the + registers between the others drivers. + menu "Multimedia Capabilities Port drivers" depends on ARCH_SA1100 diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile index dda4d4f73ad7..876ca8600c51 100644 --- a/drivers/mfd/Makefile +++ b/drivers/mfd/Makefile @@ -212,3 +212,5 @@ obj-$(CONFIG_MFD_MT6397) += mt6397-core.o obj-$(CONFIG_MFD_ALTERA_A10SR) += altera-a10sr.o obj-$(CONFIG_MFD_SUN4I_GPADC) += sun4i-gpadc.o + +obj-$(CONFIG_MFD_STM32_TIMERS) += stm32-timers.o diff --git a/drivers/mfd/stm32-timers.c b/drivers/mfd/stm32-timers.c new file mode 100644 index 000000000000..41bd9017f3d0 --- /dev/null +++ b/drivers/mfd/stm32-timers.c @@ -0,0 +1,80 @@ +/* + * Copyright (C) STMicroelectronics 2016 + * + * Author: Benjamin Gaignard <benjamin.gaignard@st.com> + * + * License terms: GNU General Public License (GPL), version 2 + */ + +#include <linux/mfd/stm32-timers.h> +#include <linux/module.h> +#include <linux/of_platform.h> +#include <linux/reset.h> + +static const struct regmap_config stm32_timers_regmap_cfg = { + .reg_bits = 32, + .val_bits = 32, + .reg_stride = sizeof(u32), + .max_register = 0x400, +}; + +static void stm32_timers_get_arr_size(struct stm32_timers *ddata) +{ + /* + * Only the available bits will be written so when readback + * we get the maximum value of auto reload register + */ + regmap_write(ddata->regmap, TIM_ARR, ~0L); + regmap_read(ddata->regmap, TIM_ARR, &ddata->max_arr); + regmap_write(ddata->regmap, TIM_ARR, 0x0); +} + +static int stm32_timers_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct stm32_timers *ddata; + struct resource *res; + void __iomem *mmio; + + ddata = devm_kzalloc(dev, sizeof(*ddata), GFP_KERNEL); + if (!ddata) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + mmio = devm_ioremap_resource(dev, res); + if (IS_ERR(mmio)) + return PTR_ERR(mmio); + + ddata->regmap = devm_regmap_init_mmio_clk(dev, "int", mmio, + &stm32_timers_regmap_cfg); + if (IS_ERR(ddata->regmap)) + return PTR_ERR(ddata->regmap); + + ddata->clk = devm_clk_get(dev, NULL); + if (IS_ERR(ddata->clk)) + return PTR_ERR(ddata->clk); + + stm32_timers_get_arr_size(ddata); + + platform_set_drvdata(pdev, ddata); + + return of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev); +} + +static const struct of_device_id stm32_timers_of_match[] = { + { .compatible = "st,stm32-timers", }, + { /* end node */ }, +}; +MODULE_DEVICE_TABLE(of, stm32_timers_of_match); + +static struct platform_driver stm32_timers_driver = { + .probe = stm32_timers_probe, + .driver = { + .name = "stm32-timers", + .of_match_table = stm32_timers_of_match, + }, +}; +module_platform_driver(stm32_timers_driver); + +MODULE_DESCRIPTION("STMicroelectronics STM32 Timers"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig index f92dd41b0395..2d0cfaa6d84c 100644 --- a/drivers/pwm/Kconfig +++ b/drivers/pwm/Kconfig @@ -397,6 +397,15 @@ config PWM_STI To compile this driver as a module, choose M here: the module will be called pwm-sti. +config PWM_STM32 + tristate "STMicroelectronics STM32 PWM" + depends on MFD_STM32_TIMERS || COMPILE_TEST + help + Generic PWM framework driver for STM32 SoCs. + + To compile this driver as a module, choose M here: the module + will be called pwm-stm32. + config PWM_STMPE bool "STMPE expander PWM export" depends on MFD_STMPE diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile index a48bdb517792..346a83b00f28 100644 --- a/drivers/pwm/Makefile +++ b/drivers/pwm/Makefile @@ -38,6 +38,7 @@ obj-$(CONFIG_PWM_ROCKCHIP) += pwm-rockchip.o obj-$(CONFIG_PWM_SAMSUNG) += pwm-samsung.o obj-$(CONFIG_PWM_SPEAR) += pwm-spear.o obj-$(CONFIG_PWM_STI) += pwm-sti.o +obj-$(CONFIG_PWM_STM32) += pwm-stm32.o obj-$(CONFIG_PWM_STMPE) += pwm-stmpe.o obj-$(CONFIG_PWM_SUN4I) += pwm-sun4i.o obj-$(CONFIG_PWM_TEGRA) += pwm-tegra.o diff --git a/drivers/pwm/pwm-stm32.c b/drivers/pwm/pwm-stm32.c new file mode 100644 index 000000000000..6139512aab7b --- /dev/null +++ b/drivers/pwm/pwm-stm32.c @@ -0,0 +1,397 @@ +/* + * Copyright (C) STMicroelectronics 2016 + * + * Author: Gerald Baeza <gerald.baeza@st.com> + * + * License terms: GNU General Public License (GPL), version 2 + * + * Inspired by timer-stm32.c from Maxime Coquelin + * pwm-atmel.c from Bo Shen + */ + +#include <linux/mfd/stm32-timers.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/pwm.h> + +#define CCMR_CHANNEL_SHIFT 8 +#define CCMR_CHANNEL_MASK 0xFF +#define MAX_BREAKINPUT 2 + +struct stm32_pwm { + struct pwm_chip chip; + struct device *dev; + struct clk *clk; + struct regmap *regmap; + u32 max_arr; + bool have_complementary_output; +}; + +struct stm32_breakinput { + u32 index; + u32 level; + u32 filter; +}; + +static inline struct stm32_pwm *to_stm32_pwm_dev(struct pwm_chip *chip) +{ + return container_of(chip, struct stm32_pwm, chip); +} + +static u32 active_channels(struct stm32_pwm *dev) +{ + u32 ccer; + + regmap_read(dev->regmap, TIM_CCER, &ccer); + + return ccer & TIM_CCER_CCXE; +} + +static int write_ccrx(struct stm32_pwm *dev, int ch, u32 value) +{ + switch (ch) { + case 0: + return regmap_write(dev->regmap, TIM_CCR1, value); + case 1: + return regmap_write(dev->regmap, TIM_CCR2, value); + case 2: + return regmap_write(dev->regmap, TIM_CCR3, value); + case 3: + return regmap_write(dev->regmap, TIM_CCR4, value); + } + return -EINVAL; +} + +static int stm32_pwm_config(struct stm32_pwm *priv, int ch, + int duty_ns, int period_ns) +{ + unsigned long long prd, div, dty; + unsigned int prescaler = 0; + u32 ccmr, mask, shift; + + /* Period and prescaler values depends on clock rate */ + div = (unsigned long long)clk_get_rate(priv->clk) * period_ns; + + do_div(div, NSEC_PER_SEC); + prd = div; + + while (div > priv->max_arr) { + prescaler++; + div = prd; + do_div(div, prescaler + 1); + } + + prd = div; + + if (prescaler > MAX_TIM_PSC) + return -EINVAL; + + /* + * All channels share the same prescaler and counter so when two + * channels are active at the same time we can't change them + */ + if (active_channels(priv) & ~(1 << ch * 4)) { + u32 psc, arr; + + regmap_read(priv->regmap, TIM_PSC, &psc); + regmap_read(priv->regmap, TIM_ARR, &arr); + + if ((psc != prescaler) || (arr != prd - 1)) + return -EBUSY; + } + + regmap_write(priv->regmap, TIM_PSC, prescaler); + regmap_write(priv->regmap, TIM_ARR, prd - 1); + regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_ARPE, TIM_CR1_ARPE); + + /* Calculate the duty cycles */ + dty = prd * duty_ns; + do_div(dty, period_ns); + + write_ccrx(priv, ch, dty); + + /* Configure output mode */ + shift = (ch & 0x1) * CCMR_CHANNEL_SHIFT; + ccmr = (TIM_CCMR_PE | TIM_CCMR_M1) << shift; + mask = CCMR_CHANNEL_MASK << shift; + + if (ch < 2) + regmap_update_bits(priv->regmap, TIM_CCMR1, mask, ccmr); + else + regmap_update_bits(priv->regmap, TIM_CCMR2, mask, ccmr); + + regmap_update_bits(priv->regmap, TIM_BDTR, + TIM_BDTR_MOE | TIM_BDTR_AOE, + TIM_BDTR_MOE | TIM_BDTR_AOE); + + return 0; +} + +static int stm32_pwm_set_polarity(struct stm32_pwm *priv, int ch, + enum pwm_polarity polarity) +{ + u32 mask; + + mask = TIM_CCER_CC1P << (ch * 4); + if (priv->have_complementary_output) + mask |= TIM_CCER_CC1NP << (ch * 4); + + regmap_update_bits(priv->regmap, TIM_CCER, mask, + polarity == PWM_POLARITY_NORMAL ? 0 : mask); + + return 0; +} + +static int stm32_pwm_enable(struct stm32_pwm *priv, int ch) +{ + u32 mask; + int ret; + + ret = clk_enable(priv->clk); + if (ret) + return ret; + + /* Enable channel */ + mask = TIM_CCER_CC1E << (ch * 4); + if (priv->have_complementary_output) + mask |= TIM_CCER_CC1NE << (ch * 4); + + regmap_update_bits(priv->regmap, TIM_CCER, mask, mask); + + /* Make sure that registers are updated */ + regmap_update_bits(priv->regmap, TIM_EGR, TIM_EGR_UG, TIM_EGR_UG); + + /* Enable controller */ + regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, TIM_CR1_CEN); + + return 0; +} + +static void stm32_pwm_disable(struct stm32_pwm *priv, int ch) +{ + u32 mask; + + /* Disable channel */ + mask = TIM_CCER_CC1E << (ch * 4); + if (priv->have_complementary_output) + mask |= TIM_CCER_CC1NE << (ch * 4); + + regmap_update_bits(priv->regmap, TIM_CCER, mask, 0); + + /* When all channels are disabled, we can disable the controller */ + if (!active_channels(priv)) + regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, 0); + + clk_disable(priv->clk); +} + +static int stm32_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, + struct pwm_state *state) +{ + bool enabled; + struct stm32_pwm *priv = to_stm32_pwm_dev(chip); + int ret; + + enabled = pwm->state.enabled; + + if (enabled && !state->enabled) { + stm32_pwm_disable(priv, pwm->hwpwm); + return 0; + } + + if (state->polarity != pwm->state.polarity) + stm32_pwm_set_polarity(priv, pwm->hwpwm, state->polarity); + + ret = stm32_pwm_config(priv, pwm->hwpwm, + state->duty_cycle, state->period); + if (ret) + return ret; + + if (!enabled && state->enabled) + ret = stm32_pwm_enable(priv, pwm->hwpwm); + + return ret; +} + +static const struct pwm_ops stm32pwm_ops = { + .owner = THIS_MODULE, + .apply = stm32_pwm_apply, +}; + +static int stm32_pwm_set_breakinput(struct stm32_pwm *priv, + int index, int level, int filter) +{ + u32 bke = (index == 0) ? TIM_BDTR_BKE : TIM_BDTR_BK2E; + int shift = (index == 0) ? TIM_BDTR_BKF_SHIFT : TIM_BDTR_BK2F_SHIFT; + u32 mask = (index == 0) ? TIM_BDTR_BKE | TIM_BDTR_BKP | TIM_BDTR_BKF + : TIM_BDTR_BK2E | TIM_BDTR_BK2P | TIM_BDTR_BK2F; + u32 bdtr = bke; + + /* + * The both bits could be set since only one will be wrote + * due to mask value. + */ + if (level) + bdtr |= TIM_BDTR_BKP | TIM_BDTR_BK2P; + + bdtr |= (filter & TIM_BDTR_BKF_MASK) << shift; + + regmap_update_bits(priv->regmap, TIM_BDTR, mask, bdtr); + + regmap_read(priv->regmap, TIM_BDTR, &bdtr); + + return (bdtr & bke) ? 0 : -EINVAL; +} + +static int stm32_pwm_apply_breakinputs(struct stm32_pwm *priv, + struct device_node *np) +{ + struct stm32_breakinput breakinput[MAX_BREAKINPUT]; + int nb, ret, i, array_size; + + nb = of_property_count_elems_of_size(np, "st,breakinput", + sizeof(struct stm32_breakinput)); + + /* + * Because "st,breakinput" parameter is optional do not make probe + * failed if it doesn't exist. + */ + if (nb <= 0) + return 0; + + if (nb > MAX_BREAKINPUT) + return -EINVAL; + + array_size = nb * sizeof(struct stm32_breakinput) / sizeof(u32); + ret = of_property_read_u32_array(np, "st,breakinput", + (u32 *)breakinput, array_size); + if (ret) + return ret; + + for (i = 0; i < nb && !ret; i++) { + ret = stm32_pwm_set_breakinput(priv, + breakinput[i].index, + breakinput[i].level, + breakinput[i].filter); + } + + return ret; +} + +static void stm32_pwm_detect_complementary(struct stm32_pwm *priv) +{ + u32 ccer; + + /* + * If complementary bit doesn't exist writing 1 will have no + * effect so we can detect it. + */ + regmap_update_bits(priv->regmap, + TIM_CCER, TIM_CCER_CC1NE, TIM_CCER_CC1NE); + regmap_read(priv->regmap, TIM_CCER, &ccer); + regmap_update_bits(priv->regmap, TIM_CCER, TIM_CCER_CC1NE, 0); + + priv->have_complementary_output = (ccer != 0); +} + +static int stm32_pwm_detect_channels(struct stm32_pwm *priv) +{ + u32 ccer; + int npwm = 0; + + /* + * If channels enable bits don't exist writing 1 will have no + * effect so we can detect and count them. + */ + regmap_update_bits(priv->regmap, + TIM_CCER, TIM_CCER_CCXE, TIM_CCER_CCXE); + regmap_read(priv->regmap, TIM_CCER, &ccer); + regmap_update_bits(priv->regmap, TIM_CCER, TIM_CCER_CCXE, 0); + + if (ccer & TIM_CCER_CC1E) + npwm++; + + if (ccer & TIM_CCER_CC2E) + npwm++; + + if (ccer & TIM_CCER_CC3E) + npwm++; + + if (ccer & TIM_CCER_CC4E) + npwm++; + + return npwm; +} + +static int stm32_pwm_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct device_node *np = dev->of_node; + struct stm32_timers *ddata = dev_get_drvdata(pdev->dev.parent); + struct stm32_pwm *priv; + int ret; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->regmap = ddata->regmap; + priv->clk = ddata->clk; + priv->max_arr = ddata->max_arr; + + if (!priv->regmap || !priv->clk) + return -EINVAL; + + ret = stm32_pwm_apply_breakinputs(priv, np); + if (ret) + return ret; + + stm32_pwm_detect_complementary(priv); + + priv->chip.base = -1; + priv->chip.dev = dev; + priv->chip.ops = &stm32pwm_ops; + priv->chip.npwm = stm32_pwm_detect_channels(priv); + + ret = pwmchip_add(&priv->chip); + if (ret < 0) + return ret; + + platform_set_drvdata(pdev, priv); + + return 0; +} + +static int stm32_pwm_remove(struct platform_device *pdev) +{ + struct stm32_pwm *priv = platform_get_drvdata(pdev); + unsigned int i; + + for (i = 0; i < priv->chip.npwm; i++) + pwm_disable(&priv->chip.pwms[i]); + + pwmchip_remove(&priv->chip); + + return 0; +} + +static const struct of_device_id stm32_pwm_of_match[] = { + { .compatible = "st,stm32-pwm", }, + { /* end node */ }, +}; +MODULE_DEVICE_TABLE(of, stm32_pwm_of_match); + +static struct platform_driver stm32_pwm_driver = { + .probe = stm32_pwm_probe, + .remove = stm32_pwm_remove, + .driver = { + .name = "stm32-pwm", + .of_match_table = stm32_pwm_of_match, + }, +}; +module_platform_driver(stm32_pwm_driver); + +MODULE_ALIAS("platform:stm32-pwm"); +MODULE_DESCRIPTION("STMicroelectronics STM32 PWM driver"); +MODULE_LICENSE("GPL v2"); |