[PATCH v4 2/7] MFD: add STM32 General Purpose Timer driver
Benjamin Gaignard
benjamin.gaignard at linaro.org
Tue Dec 6 04:38:44 PST 2016
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 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 at st.com>
---
drivers/mfd/Kconfig | 11 ++++++
drivers/mfd/Makefile | 2 +
drivers/mfd/stm32-gptimer.c | 82 +++++++++++++++++++++++++++++++++++++++
include/linux/mfd/stm32-gptimer.h | 63 ++++++++++++++++++++++++++++++
4 files changed, 158 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..a00f6b3 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"
+ select MFD_CORE
+ select REGMAP
+ depends on ARCH_STM32 || COMPILE_TEST
+ depends on OF
+ 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..6747fcb
--- /dev/null
+++ b/drivers/mfd/stm32-gptimer.c
@@ -0,0 +1,82 @@
+/*
+ * Copyright (C) STMicroelectronics 2016
+ *
+ * Author: Benjamin Gaignard <benjamin.gaignard at st.com>
+ * License terms: GNU General Public License (GPL), version 2
+ */
+
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/reset.h>
+
+#include <linux/mfd/stm32-gptimer.h>
+
+static const struct regmap_config stm32_gptimer_regmap_cfg = {
+ .reg_bits = 32,
+ .val_bits = 32,
+ .reg_stride = sizeof(u32),
+ .max_register = 0x400,
+};
+
+static u32 stm32_gptimer_get_arr_size(struct regmap *regmap)
+{
+ u32 max_arr;
+
+ /* Only the available bits will be written so when readback
+ * we get the maximum value of auto reload register
+ */
+ regmap_write(regmap, TIM_ARR, ~0L);
+ regmap_read(regmap, TIM_ARR, &max_arr);
+ regmap_write(regmap, TIM_ARR, 0x0);
+
+ return max_arr;
+}
+
+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);
+
+ ddata->max_arr = stm32_gptimer_get_arr_size(ddata->regmap);
+
+ 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" },
+};
+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..bf0a595
--- /dev/null
+++ b/include/linux/mfd/stm32-gptimer.h
@@ -0,0 +1,63 @@
+/*
+ * Copyright (C) STMicroelectronics 2016
+ *
+ * Author: Benjamin Gaignard <benjamin.gaignard at 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
--
1.9.1
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