This hardware block could at used at same time for PWM generation and IIO timers. PWM and IIO timer configuration are mixed in the same registers so we need a multi fonction driver to be able to share those registers.
version 5: - fix Lee comments about detect function - add missing dependency on REGMAP_MMIO
version 4: - add a function to detect Auto Reload Register (ARR) size - rename the structure shared with other drivers
version 2: - rename driver "stm32-gptimer" to be align with SoC documentation - only keep one compatible - use of_platform_populate() instead of devm_mfd_add_devices()
Signed-off-by: Benjamin Gaignard benjamin.gaignard@st.com --- drivers/mfd/Kconfig | 11 ++++++ drivers/mfd/Makefile | 2 + drivers/mfd/stm32-gptimer.c | 80 +++++++++++++++++++++++++++++++++++++++ include/linux/mfd/stm32-gptimer.h | 64 +++++++++++++++++++++++++++++++ 4 files changed, 157 insertions(+) create mode 100644 drivers/mfd/stm32-gptimer.c create mode 100644 include/linux/mfd/stm32-gptimer.h
diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig index c6df644..b797312 100644 --- a/drivers/mfd/Kconfig +++ b/drivers/mfd/Kconfig @@ -1607,6 +1607,17 @@ config MFD_STW481X in various ST Microelectronics and ST-Ericsson embedded Nomadik series.
+config MFD_STM32_GP_TIMER + tristate "Support for STM32 General Purpose Timer" + depends on (ARCH_STM32 && OF) || COMPILE_TEST + select MFD_CORE + select REGMAP + select REGMAP_MMIO + help + Select this option to enable STM32 general purpose timer + 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 9834e66..86353b9 100644 --- a/drivers/mfd/Makefile +++ b/drivers/mfd/Makefile @@ -211,3 +211,5 @@ obj-$(CONFIG_INTEL_SOC_PMIC) += intel-soc-pmic.o obj-$(CONFIG_MFD_MT6397) += mt6397-core.o
obj-$(CONFIG_MFD_ALTERA_A10SR) += altera-a10sr.o + +obj-$(CONFIG_MFD_STM32_GP_TIMER) += stm32-gptimer.o diff --git a/drivers/mfd/stm32-gptimer.c b/drivers/mfd/stm32-gptimer.c new file mode 100644 index 0000000..0642f1a --- /dev/null +++ b/drivers/mfd/stm32-gptimer.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-gptimer.h> +#include <linux/module.h> +#include <linux/of_platform.h> +#include <linux/reset.h> + +static const struct regmap_config stm32_gptimer_regmap_cfg = { + .reg_bits = 32, + .val_bits = 32, + .reg_stride = sizeof(u32), + .max_register = 0x400, +}; + +static void stm32_gptimer_get_arr_size(struct stm32_gptimer *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_gptimer_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct stm32_gptimer *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, "clk_int", mmio, + &stm32_gptimer_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_gptimer_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_gptimer_of_match[] = { + { .compatible = "st,stm32-gptimer", }, + { /* sentinelle */ }, +}; +MODULE_DEVICE_TABLE(of, stm32_gptimer_of_match); + +static struct platform_driver stm32_gptimer_driver = { + .probe = stm32_gptimer_probe, + .driver = { + .name = "stm32-gptimer", + .of_match_table = stm32_gptimer_of_match, + }, +}; +module_platform_driver(stm32_gptimer_driver); + +MODULE_DESCRIPTION("STMicroelectronics STM32 General Purpose Timer"); +MODULE_LICENSE("GPL v2"); diff --git a/include/linux/mfd/stm32-gptimer.h b/include/linux/mfd/stm32-gptimer.h new file mode 100644 index 0000000..567a15e --- /dev/null +++ b/include/linux/mfd/stm32-gptimer.h @@ -0,0 +1,64 @@ +/* + * Copyright (C) STMicroelectronics 2016 + * + * Author: Benjamin Gaignard benjamin.gaignard@st.com + * + * License terms: GNU General Public License (GPL), version 2 + */ + +#ifndef _LINUX_STM32_GPTIMER_H_ +#define _LINUX_STM32_GPTIMER_H_ + +#include <linux/clk.h> +#include <linux/regmap.h> + +#define TIM_CR1 0x00 /* Control Register 1 */ +#define TIM_CR2 0x04 /* Control Register 2 */ +#define TIM_SMCR 0x08 /* Slave mode control reg */ +#define TIM_DIER 0x0C /* DMA/interrupt register */ +#define TIM_SR 0x10 /* Status register */ +#define TIM_EGR 0x14 /* Event Generation Reg */ +#define TIM_CCMR1 0x18 /* Capt/Comp 1 Mode Reg */ +#define TIM_CCMR2 0x1C /* Capt/Comp 2 Mode Reg */ +#define TIM_CCER 0x20 /* Capt/Comp Enable Reg */ +#define TIM_PSC 0x28 /* Prescaler */ +#define TIM_ARR 0x2c /* Auto-Reload Register */ +#define TIM_CCR1 0x34 /* Capt/Comp Register 1 */ +#define TIM_CCR2 0x38 /* Capt/Comp Register 2 */ +#define TIM_CCR3 0x3C /* Capt/Comp Register 3 */ +#define TIM_CCR4 0x40 /* Capt/Comp Register 4 */ +#define TIM_BDTR 0x44 /* Break and Dead-Time Reg */ + +#define TIM_CR1_CEN BIT(0) /* Counter Enable */ +#define TIM_CR1_ARPE BIT(7) /* Auto-reload Preload Ena */ +#define TIM_CR2_MMS (BIT(4) | BIT(5) | BIT(6)) /* Master mode selection */ +#define TIM_SMCR_SMS (BIT(0) | BIT(1) | BIT(2)) /* Slave mode selection */ +#define TIM_SMCR_TS (BIT(4) | BIT(5) | BIT(6)) /* Trigger selection */ +#define TIM_DIER_UIE BIT(0) /* Update interrupt */ +#define TIM_SR_UIF BIT(0) /* Update interrupt flag */ +#define TIM_EGR_UG BIT(0) /* Update Generation */ +#define TIM_CCMR_PE BIT(3) /* Channel Preload Enable */ +#define TIM_CCMR_M1 (BIT(6) | BIT(5)) /* Channel PWM Mode 1 */ +#define TIM_CCER_CC1E BIT(0) /* Capt/Comp 1 out Ena */ +#define TIM_CCER_CC1P BIT(1) /* Capt/Comp 1 Polarity */ +#define TIM_CCER_CC1NE BIT(2) /* Capt/Comp 1N out Ena */ +#define TIM_CCER_CC1NP BIT(3) /* Capt/Comp 1N Polarity */ +#define TIM_CCER_CC2E BIT(4) /* Capt/Comp 2 out Ena */ +#define TIM_CCER_CC3E BIT(8) /* Capt/Comp 3 out Ena */ +#define TIM_CCER_CC4E BIT(12) /* Capt/Comp 4 out Ena */ +#define TIM_CCER_CCXE (BIT(0) | BIT(4) | BIT(8) | BIT(12)) +#define TIM_BDTR_BKE BIT(12) /* Break input enable */ +#define TIM_BDTR_BKP BIT(13) /* Break input polarity */ +#define TIM_BDTR_AOE BIT(14) /* Automatic Output Enable */ +#define TIM_BDTR_MOE BIT(15) /* Main Output Enable */ + +#define MAX_TIM_PSC 0xFFFF +#define TIM_CR2_MMS_SHIFT 4 +#define TIM_SMCR_TS_SHIFT 4 + +struct stm32_gptimer { + struct clk *clk; + struct regmap *regmap; + u32 max_arr; +}; +#endif