Add bindings information for STM32 Timers

version 6: - rename stm32-gtimer to stm32-timers - change compatible - add description about the IPs

version 2: - rename stm32-mfd-timer to stm32-gptimer - only keep one compatible string

Signed-off-by: Benjamin Gaignard benjamin.gaignard@st.com Acked-by: Lee Jones lee.jones@linaro.org Acked-by: Rob Herring robh@kernel.org --- .../devicetree/bindings/mfd/stm32-timers.txt | 46 ++++++++++++++++++++++ 1 file changed, 46 insertions(+) create mode 100644 Documentation/devicetree/bindings/mfd/stm32-timers.txt

diff --git a/Documentation/devicetree/bindings/mfd/stm32-timers.txt b/Documentation/devicetree/bindings/mfd/stm32-timers.txt new file mode 100644 index 0000000..bbd083f --- /dev/null +++ b/Documentation/devicetree/bindings/mfd/stm32-timers.txt @@ -0,0 +1,46 @@ +STM32 Timers driver bindings + +This IP provides 3 types of timer along with PWM functionality: +- advanced-control timers consist of a 16-bit auto-reload counter driven by a programmable + prescaler, break input feature, PWM outputs and complementary PWM ouputs channels. +- general-purpose timers consist of a 16-bit or 32-bit auto-reload counter driven by a + programmable prescaler and PWM outputs. +- basic timers consist of a 16-bit auto-reload counter driven by a programmable prescaler. + +Required parameters: +- compatible: must be "st,stm32-timers" + +- reg: Physical base address and length of the controller's + registers. +- clock-names: Set to "int". +- clocks: Phandle to the clock used by the timer module. + For Clk properties, please refer to ../clock/clock-bindings.txt + +Optional parameters: +- resets: Phandle to the parent reset controller. + See ../reset/st,stm32-rcc.txt + +Optional subnodes: +- pwm: See ../pwm/pwm-stm32.txt +- timer: See ../iio/timer/stm32-timer-trigger.txt + +Example: + timers@40010000 { + #address-cells = <1>; + #size-cells = <0>; + compatible = "st,stm32-timers"; + reg = <0x40010000 0x400>; + clocks = <&rcc 0 160>; + clock-names = "clk_int"; + + pwm { + compatible = "st,stm32-pwm"; + pinctrl-0 = <&pwm1_pins>; + pinctrl-names = "default"; + }; + + timer@0 { + compatible = "st,stm32-timer-trigger"; + reg = <0>; + }; + };

Define bindings for pwm-stm32

version 8: - reword st,breakinput description.

version 6: - change st,breakinput parameter format to make it usuable on stm32f7 too.

version 2: - use parameters instead of compatible of handle the hardware configuration

Signed-off-by: Benjamin Gaignard benjamin.gaignard@st.com Acked-by: Rob Herring robh@kernel.org --- .../devicetree/bindings/pwm/pwm-stm32.txt | 35 ++++++++++++++++++++++ 1 file changed, 35 insertions(+) create mode 100644 Documentation/devicetree/bindings/pwm/pwm-stm32.txt

diff --git a/Documentation/devicetree/bindings/pwm/pwm-stm32.txt b/Documentation/devicetree/bindings/pwm/pwm-stm32.txt new file mode 100644 index 0000000..6dd0403 --- /dev/null +++ b/Documentation/devicetree/bindings/pwm/pwm-stm32.txt @@ -0,0 +1,35 @@ +STMicroelectronics STM32 Timers PWM bindings + +Must be a sub-node of an STM32 Timers device tree node. +See ../mfd/stm32-timers.txt for details about the parent node. + +Required parameters: +- compatible: Must be "st,stm32-pwm". +- pinctrl-names: Set to "default". +- pinctrl-0: List of phandles pointing to pin configuration nodes for PWM module. + For Pinctrl properties see ../pinctrl/pinctrl-bindings.txt + +Optional parameters: +- st,breakinput: One or two <index level filter> to describe break input configurations. + "index" indicates on which break input (0 or 1) the configuration + should be applied. + "level" gives the active level (0=low or 1=high) of the input signal + for this configuration. + "filter" gives the filtering value to be applied. + +Example: + timers@40010000 { + #address-cells = <1>; + #size-cells = <0>; + compatible = "st,stm32-timers"; + reg = <0x40010000 0x400>; + clocks = <&rcc 0 160>; + clock-names = "clk_int"; + + pwm { + compatible = "st,stm32-pwm"; + pinctrl-0 = <&pwm1_pins>; + pinctrl-names = "default"; + st,breakinput = <0 1 5>; + }; + };

This driver adds support for PWM driver on STM32 platform. The SoC have multiple instances of the hardware IP and each of them could have small differences: number of channels, complementary output, auto reload register size...

version 8: - fix comments done by Thierry on version 7

version 6: - change st,breakinput parameter to make it usuable for stm32f7 too.

version 4: - detect at probe time hardware capabilities - fix comments done on v2 and v3 - use PWM atomic ops

version 2: - only keep one comptatible - use DT parameters to discover hardware block configuration

Signed-off-by: Benjamin Gaignard benjamin.gaignard@st.com --- drivers/pwm/Kconfig | 9 ++ drivers/pwm/Makefile | 1 + drivers/pwm/pwm-stm32.c | 398 ++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 408 insertions(+) create mode 100644 drivers/pwm/pwm-stm32.c

diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig index f92dd41..2d0cfaa 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 a48bdb5..346a83b 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 0000000..3780afd --- /dev/null +++ b/drivers/pwm/pwm-stm32.c @@ -0,0 +1,398 @@ +/* + * 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) +{ + struct pwm_state curstate; + 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 != curstate.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");

Define bindings for STM32 timer trigger

version 8: - reword "reg" parameter description

version 4: - remove triggers enumeration from DT - add reg parameter

version 3: - change file name - add cross reference with mfd bindings

version 2: - only keep one compatible - add DT parameters to set lists of the triggers: one list describe the triggers created by the device another one give the triggers accepted by the device

Signed-off-by: Benjamin Gaignard benjamin.gaignard@st.com Acked-by: Jonathan Cameron jic23@kernel.org --- .../bindings/iio/timer/stm32-timer-trigger.txt | 23 ++++++++++++++++++++++ 1 file changed, 23 insertions(+) create mode 100644 Documentation/devicetree/bindings/iio/timer/stm32-timer-trigger.txt

diff --git a/Documentation/devicetree/bindings/iio/timer/stm32-timer-trigger.txt b/Documentation/devicetree/bindings/iio/timer/stm32-timer-trigger.txt new file mode 100644 index 0000000..55a653d --- /dev/null +++ b/Documentation/devicetree/bindings/iio/timer/stm32-timer-trigger.txt @@ -0,0 +1,23 @@ +STMicroelectronics STM32 Timers IIO timer bindings + +Must be a sub-node of an STM32 Timers device tree node. +See ../mfd/stm32-timers.txt for details about the parent node. + +Required parameters: +- compatible: Must be "st,stm32-timer-trigger". +- reg: Identify trigger hardware block. + +Example: + timers@40010000 { + #address-cells = <1>; + #size-cells = <0>; + compatible = "st,stm32-timers"; + reg = <0x40010000 0x400>; + clocks = <&rcc 0 160>; + clock-names = "clk_int"; + + timer@0 { + compatible = "st,stm32-timer-trigger"; + reg = <0>; + }; + };

Timers IPs can be used to generate triggers for other IPs like DAC or ADC. Each trigger may result of timer internals signals like counter enable, reset or edge, this configuration could be done through "master_mode" device attribute.

Since triggers could be used by DAC or ADC their names are defined in include/ nux/iio/timer/stm32-timer-trigger.h and is_stm32_iio_timer_trigger function could be used to check if the trigger is valid or not.

"trgo" trigger have a "sampling_frequency" attribute which allow to configure timer sampling frequency.

version 8: - change kernel version from 4.10 to 4.11 in ABI documentation

version 7: - remove all iio_device related code - move driver into trigger directory

version 5: - simplify tables of triggers - only create an IIO device when needed

version 4: - get triggers configuration from "reg" in DT - add tables of triggers - sampling frequency is enable/disable when writing in trigger sampling_frequency attribute - no more use of interruptions

version 3: - change compatible to "st,stm32-timer-trigger" - fix attributes access right - use string instead of int for master_mode and slave_mode - document device attributes in sysfs-bus-iio-timer-stm32

version 2: - keep only one compatible - use st,input-triggers-names and st,output-triggers-names to know which triggers are accepted and/or create by the device

Signed-off-by: Benjamin Gaignard benjamin.gaignard@st.com Acked-by: Jonathan Cameron jic23@kernel.org --- .../ABI/testing/sysfs-bus-iio-timer-stm32 | 29 ++ drivers/iio/trigger/Kconfig | 9 + drivers/iio/trigger/Makefile | 1 + drivers/iio/trigger/stm32-timer-trigger.c | 342 +++++++++++++++++++++ include/linux/iio/timer/stm32-timer-trigger.h | 62 ++++ 5 files changed, 443 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-bus-iio-timer-stm32 create mode 100644 drivers/iio/trigger/stm32-timer-trigger.c create mode 100644 include/linux/iio/timer/stm32-timer-trigger.h

diff --git a/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32 b/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32 new file mode 100644 index 0000000..6534a60 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32 @@ -0,0 +1,29 @@ +What: /sys/bus/iio/devices/triggerX/master_mode_available +KernelVersion: 4.11 +Contact: benjamin.gaignard@st.com +Description: + Reading returns the list possible master modes which are: + - "reset" : The UG bit from the TIMx_EGR register is used as trigger output (TRGO). + - "enable" : The Counter Enable signal CNT_EN is used as trigger output. + - "update" : The update event is selected as trigger output. + For instance a master timer can then be used as a prescaler for a slave timer. + - "compare_pulse" : The trigger output send a positive pulse when the CC1IF flag is to be set. + - "OC1REF" : OC1REF signal is used as trigger output. + - "OC2REF" : OC2REF signal is used as trigger output. + - "OC3REF" : OC3REF signal is used as trigger output. + - "OC4REF" : OC4REF signal is used as trigger output. + +What: /sys/bus/iio/devices/triggerX/master_mode +KernelVersion: 4.11 +Contact: benjamin.gaignard@st.com +Description: + Reading returns the current master modes. + Writing set the master mode + +What: /sys/bus/iio/devices/triggerX/sampling_frequency +KernelVersion: 4.11 +Contact: benjamin.gaignard@st.com +Description: + Reading returns the current sampling frequency. + Writing an value different of 0 set and start sampling. + Writing 0 stop sampling. diff --git a/drivers/iio/trigger/Kconfig b/drivers/iio/trigger/Kconfig index 809b2e7..e4d4e63 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 aab4dc2..5c4ecd3 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 0000000..994b96d --- /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/include/linux/iio/timer/stm32-timer-trigger.h b/include/linux/iio/timer/stm32-timer-trigger.h new file mode 100644 index 0000000..55535ae --- /dev/null +++ b/include/linux/iio/timer/stm32-timer-trigger.h @@ -0,0 +1,62 @@ +/* + * Copyright (C) STMicroelectronics 2016 + * + * Author: Benjamin Gaignard benjamin.gaignard@st.com + * + * License terms: GNU General Public License (GPL), version 2 + */ + +#ifndef _STM32_TIMER_TRIGGER_H_ +#define _STM32_TIMER_TRIGGER_H_ + +#define TIM1_TRGO "tim1_trgo" +#define TIM1_CH1 "tim1_ch1" +#define TIM1_CH2 "tim1_ch2" +#define TIM1_CH3 "tim1_ch3" +#define TIM1_CH4 "tim1_ch4" + +#define TIM2_TRGO "tim2_trgo" +#define TIM2_CH1 "tim2_ch1" +#define TIM2_CH2 "tim2_ch2" +#define TIM2_CH3 "tim2_ch3" +#define TIM2_CH4 "tim2_ch4" + +#define TIM3_TRGO "tim3_trgo" +#define TIM3_CH1 "tim3_ch1" +#define TIM3_CH2 "tim3_ch2" +#define TIM3_CH3 "tim3_ch3" +#define TIM3_CH4 "tim3_ch4" + +#define TIM4_TRGO "tim4_trgo" +#define TIM4_CH1 "tim4_ch1" +#define TIM4_CH2 "tim4_ch2" +#define TIM4_CH3 "tim4_ch3" +#define TIM4_CH4 "tim4_ch4" + +#define TIM5_TRGO "tim5_trgo" +#define TIM5_CH1 "tim5_ch1" +#define TIM5_CH2 "tim5_ch2" +#define TIM5_CH3 "tim5_ch3" +#define TIM5_CH4 "tim5_ch4" + +#define TIM6_TRGO "tim6_trgo" + +#define TIM7_TRGO "tim7_trgo" + +#define TIM8_TRGO "tim8_trgo" +#define TIM8_CH1 "tim8_ch1" +#define TIM8_CH2 "tim8_ch2" +#define TIM8_CH3 "tim8_ch3" +#define TIM8_CH4 "tim8_ch4" + +#define TIM9_TRGO "tim9_trgo" +#define TIM9_CH1 "tim9_ch1" +#define TIM9_CH2 "tim9_ch2" + +#define TIM12_TRGO "tim12_trgo" +#define TIM12_CH1 "tim12_ch1" +#define TIM12_CH2 "tim12_ch2" + +bool is_stm32_timer_trigger(struct iio_trigger *trig); + +#endif

Define and enable pwm1 and pwm3 for stm32f469 discovery board

Signed-off-by: Benjamin Gaignard benjamin.gaignard@st.com --- arch/arm/boot/dts/stm32f469-disco.dts | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+)

diff --git a/arch/arm/boot/dts/stm32f469-disco.dts b/arch/arm/boot/dts/stm32f469-disco.dts index 8a163d7..92552d3 100644 --- a/arch/arm/boot/dts/stm32f469-disco.dts +++ b/arch/arm/boot/dts/stm32f469-disco.dts @@ -81,3 +81,31 @@ &usart3 { status = "okay"; }; + +&timers1 { + status = "okay"; + + pwm { + pinctrl-0 = <&pwm1_pins>; + pinctrl-names = "default"; + status = "okay"; + }; + + timer@0 { + status = "okay"; + }; +}; + +&timers3 { + status = "okay"; + + pwm { + pinctrl-0 = <&pwm3_pins>; + pinctrl-names = "default"; + status = "okay"; + }; + + timer@2 { + status = "okay"; + }; +};