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[PATCH v6 0/8] Add PWM and IIO timer drivers for STM32

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  [PATCH v6 0/8] Add PWM and IIO timer drivers for STM32 Benjamin Gaignard <benjamin.gaignard@linaro.org> - 2016-12-09 15:20 +0100
    [PATCH v6 7/8] ARM: dts: stm32: add Timers driver for stm32f429 MCU Benjamin Gaignard <benjamin.gaignard@linaro.org> - 2016-12-09 15:20 +0100
    [PATCH v6 4/8] PWM: add PWM driver for STM32 plaftorm Benjamin Gaignard <benjamin.gaignard@linaro.org> - 2016-12-09 15:20 +0100
    [PATCH v6 1/8] MFD: add bindings for STM32 Timers driver Benjamin Gaignard <benjamin.gaignard@linaro.org> - 2016-12-09 15:20 +0100
    [PATCH v6 8/8] ARM: dts: stm32: Enable pw1 and pwm3 for stm32f469-disco Benjamin Gaignard <benjamin.gaignard@linaro.org> - 2016-12-09 15:20 +0100

#1539380 — [PATCH v6 0/8] Add PWM and IIO timer drivers for STM32

version 6:
- rename stm32-gptimer in stm32-timers.
- change "st,stm32-gptimer" compatible to "st,stm32-timers".
- modify "st,breakinput" parameter in pwm part.
- split DT patch in 2

version 5:
- fix comments done on version 4
- rebased on kernel 4.9-rc8
- change nodes names and re-order then by addresses

version 4:
- fix comments done on version 3
- don't use interrupts anymore in IIO timer
- detect hardware capabilities at probe time to simplify binding

version 3:
- no change on mfd and pwm divers patches
- add cross reference between bindings
- change compatible to "st,stm32-timer-trigger"
- fix attributes access rights
- use string instead of int for master_mode and slave_mode
- document device attributes in sysfs-bus-iio-timer-stm32
- update DT with the new compatible

version 2:
- keep only one compatible per driver
- use DT parameters to describe hardware block configuration:
  - pwm channels, complementary output, counter size, break input
  - triggers accepted and create by IIO timers
- change DT to limite use of reference to the node
- interrupt is now in IIO timer driver
- rename stm32-mfd-timer to stm32-timers (for general purpose timer)

The following patches enable PWM and IIO Timer features for STM32 platforms.

Those two features are mixed into the registers of the same hardware block
(named general purpose timer) which lead to introduce a multifunctions driver 
on the top of them to be able to share the registers.

In STM32f4 14 instances of timer hardware block exist, even if they all have
the same register mapping they could have a different number of pwm channels
and/or different triggers capabilities. We use various parameters in DT to 
describe the differences between hardware blocks

The MFD (stm32-timers.c) takes care of clock and register mapping
by using regmap. stm32_timers structure is provided to its sub-node to
share those information.

PWM driver is implemented into pwm-stm32.c. Depending of the instance we may
have up to 4 channels, sometime with complementary outputs or 32 bits counter
instead of 16 bits. Some hardware blocks may also have a break input function
which allows to stop pwm depending of a level, defined in devicetree, on an
external pin.

IIO timer driver (stm32-timer-trigger.c and stm32-timer-trigger.h) define a list
of hardware triggers usable by hardware blocks like ADC, DAC or other timers. 

The matrix of possible connections between blocks is quite complex so we use 
trigger names and is_stm32_iio_timer_trigger() function to be sure that
triggers are valid and configure the IPs.

At run time IIO timer hardware blocks can configure (through "master_mode" 
IIO device attribute) which internal signal (counter enable, reset,
comparison block, etc...) is used to generate the trigger.

By using "slave_mode" IIO device attribute timer can also configure on which
event (level, rising edge) of the block is enabled.

Since we can use trigger from one hardware to control an other block, we can
use a pwm to control an other one. The following example shows how to configure
pwm1 and pwm3 to make pwm3 generate pulse only when pwm1 pulse level is high.

/sys/bus/iio/devices # ls
iio:device0  iio:device1  trigger0     trigger1

configure timer1 to use pwm1 channel 0 as output trigger
/sys/bus/iio/devices # echo 'OC1REF' > iio\:device0/master_mode
configure timer3 to enable only when input is high
/sys/bus/iio/devices # echo 'gated' > iio\:device1/slave_mode
/sys/bus/iio/devices # cat trigger0/name
tim1_trgo
configure timer2 to use timer1 trigger is input
/sys/bus/iio/devices # echo "tim1_trgo" > iio\:device1/trigger/current_trigger

configure pwm3 channel 0 to generate a signal with a period of 100ms and a
duty cycle of 50%
/sys/devices/platform/soc/40000400.timers/40000400.timers:pwm/pwm/pwmchip4 # echo 0 > export
/sys/devices/platform/soc/40000400.timers/40000400.timers:pwm/pwm/pwmchip4 # echo 100000000 > pwm0/period
/sys/devices/platform/soc/40000400.timers/40000400.timers:pwm/pwm/pwmchip4 # echo 50000000 > pwm0/duty_cycle
/sys/devices/platform/soc/40000400.timers/40000400.timers:pwm/pwm/pwmchip4 # echo 1 > pwm0/enable
here pwm3 channel 0, as expected, doesn't start because has to be triggered by
pwm1 channel 0

configure pwm1 channel 0 to generate a signal with a period of 1s and a
duty cycle of 50%
/sys/devices/platform/soc/40010000.timers/40010000.timers:pwm/pwm/pwmchip0 # echo 0 > export
/sys/devices/platform/soc/40010000.timers/40010000.timers:pwm/pwm/pwmchip0 # echo 1000000000 > pwm0/period
/sys/devices/platform/soc/40010000.timers/40010000.timers:pwm/pwm/pwmchip0 # echo 500000000 > pwm0/duty_cycle
/sys/devices/platform/soc/40010000.timers/40010000.timers:pwm/pwm/pwmchip0 # echo 1 > pwm0/enable 
finally pwm1 starts and pwm3 only generates pulse when pwm1 signal is high

An other example to use a timer as source of clock for another device.
Here timer1 is used a source clock for pwm3:

/sys/bus/iio/devices # echo 100000 > trigger0/sampling_frequency 
/sys/bus/iio/devices # echo "tim1_trgo" > iio\:device1/trigger/current_trigger 
/sys/bus/iio/devices # echo 'external_clock' > iio\:device1/slave_mode
/sys/devices/platform/soc/40000400.timers/40000400.timers:pwm/pwm/pwmchip4 # echo 0 > export 
/sys/devices/platform/soc/40000400.timers/40000400.timers:pwm/pwm/pwmchip4 # echo 1000000 > pwm0/period 
/sys/devices/platform/soc/40000400.timers/40000400.timers:pwm/pwm/pwmchip4 # echo 500000 > pwm0/duty_cycle 
/sys/devices/platform/soc/40000400.timers/40000400.timers:pwm/pwm/pwmchip4 # echo 1 > pwm0/enable

Benjamin Gaignard (8):
  MFD: add bindings for STM32 Timers driver
  MFD: add STM32 Timers driver
  PWM: add pwm-stm32 DT bindings
  PWM: add PWM driver for STM32 plaftorm
  IIO: add bindings for STM32 timer trigger driver
  IIO: add STM32 timer trigger driver
  ARM: dts: stm32: add Timers driver for stm32f429 MCU
  ARM: dts: stm32: Enable pw1 and pwm3 for stm32f469-disco

 .../ABI/testing/sysfs-bus-iio-timer-stm32          |  55 +++
 .../bindings/iio/timer/stm32-timer-trigger.txt     |  23 +
 .../devicetree/bindings/mfd/stm32-timers.txt       |  46 ++
 .../devicetree/bindings/pwm/pwm-stm32.txt          |  33 ++
 arch/arm/boot/dts/stm32f429.dtsi                   | 275 ++++++++++++
 arch/arm/boot/dts/stm32f469-disco.dts              |  28 ++
 drivers/iio/Kconfig                                |   2 +-
 drivers/iio/Makefile                               |   1 +
 drivers/iio/timer/Kconfig                          |  13 +
 drivers/iio/timer/Makefile                         |   1 +
 drivers/iio/timer/stm32-timer-trigger.c            | 466 +++++++++++++++++++++
 drivers/iio/trigger/Kconfig                        |   1 -
 drivers/mfd/Kconfig                                |  11 +
 drivers/mfd/Makefile                               |   2 +
 drivers/mfd/stm32-timers.c                         |  80 ++++
 drivers/pwm/Kconfig                                |   9 +
 drivers/pwm/Makefile                               |   1 +
 drivers/pwm/pwm-stm32.c                            | 434 +++++++++++++++++++
 include/linux/iio/timer/stm32-timer-trigger.h      |  62 +++
 include/linux/mfd/stm32-timers.h                   |  71 ++++
 20 files changed, 1612 insertions(+), 2 deletions(-)
 create mode 100644 Documentation/ABI/testing/sysfs-bus-iio-timer-stm32
 create mode 100644 Documentation/devicetree/bindings/iio/timer/stm32-timer-trigger.txt
 create mode 100644 Documentation/devicetree/bindings/mfd/stm32-timers.txt
 create mode 100644 Documentation/devicetree/bindings/pwm/pwm-stm32.txt
 create mode 100644 drivers/iio/timer/Kconfig
 create mode 100644 drivers/iio/timer/Makefile
 create mode 100644 drivers/iio/timer/stm32-timer-trigger.c
 create mode 100644 drivers/mfd/stm32-timers.c
 create mode 100644 drivers/pwm/pwm-stm32.c
 create mode 100644 include/linux/iio/timer/stm32-timer-trigger.h
 create mode 100644 include/linux/mfd/stm32-timers.h

-- 
1.9.1

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#1539381 — [PATCH v6 7/8] ARM: dts: stm32: add Timers driver for stm32f429 MCU

Add Timers and it sub-nodes into DT for stm32f429 family.

version 6:
- split patch in two: one for SoC family and one for stm32f469
  discovery board.

version 5:
- rename gptimer node to timers
- re-order timers node par addresses

version 4:
- remove unwanted indexing in pwm@ and timer@ node name
- use "reg" instead of additional parameters to set timer
  configuration

version 3:
- use "st,stm32-timer-trigger" in DT

version 2:
- use parameters to describe hardware capabilities
- do not use references for pwm and iio timer subnodes

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
---
 arch/arm/boot/dts/stm32f429.dtsi | 275 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 275 insertions(+)

diff --git a/arch/arm/boot/dts/stm32f429.dtsi b/arch/arm/boot/dts/stm32f429.dtsi
index bca491d..d0fb9cc 100644
--- a/arch/arm/boot/dts/stm32f429.dtsi
+++ b/arch/arm/boot/dts/stm32f429.dtsi
@@ -355,6 +355,21 @@
 					slew-rate = <2>;
 				};
 			};
+
+			pwm1_pins: pwm@1 {
+				pins {
+					pinmux = <STM32F429_PA8_FUNC_TIM1_CH1>,
+						 <STM32F429_PB13_FUNC_TIM1_CH1N>,
+						 <STM32F429_PB12_FUNC_TIM1_BKIN>;
+				};
+			};
+
+			pwm3_pins: pwm@3 {
+				pins {
+					pinmux = <STM32F429_PB4_FUNC_TIM3_CH1>,
+						 <STM32F429_PB5_FUNC_TIM3_CH2>;
+				};
+			};
 		};
 
 		rcc: rcc@40023810 {
@@ -426,6 +441,266 @@
 			interrupts = <80>;
 			clocks = <&rcc 0 38>;
 		};
+
+		timers2: timers@40000000 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			compatible = "st,stm32-timers";
+			reg = <0x40000000 0x400>;
+			clocks = <&rcc 0 128>;
+			clock-names = "clk_int";
+			status = "disabled";
+
+			pwm {
+				compatible = "st,stm32-pwm";
+				status = "disabled";
+			};
+
+			timer {
+				compatible = "st,stm32-timer-trigger";
+				reg = <1>;
+				status = "disabled";
+			};
+		};
+
+		timers3: timers@40000400 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			compatible = "st,stm32-timers";
+			reg = <0x40000400 0x400>;
+			clocks = <&rcc 0 129>;
+			clock-names = "clk_int";
+			status = "disabled";
+
+			pwm {
+				compatible = "st,stm32-pwm";
+				status = "disabled";
+			};
+
+			timer {
+				compatible = "st,stm32-timer-trigger";
+				reg = <2>;
+				status = "disabled";
+			};
+		};
+
+		timers4: timers@40000800 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			compatible = "st,stm32-timers";
+			reg = <0x40000800 0x400>;
+			clocks = <&rcc 0 130>;
+			clock-names = "clk_int";
+			status = "disabled";
+
+			pwm {
+				compatible = "st,stm32-pwm";
+				status = "disabled";
+			};
+
+			timer {
+				compatible = "st,stm32-timer-trigger";
+				reg = <3>;
+				status = "disabled";
+			};
+		};
+
+		timers5: timers@40000C00 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			compatible = "st,stm32-timers";
+			reg = <0x40000C00 0x400>;
+			clocks = <&rcc 0 131>;
+			clock-names = "clk_int";
+			status = "disabled";
+
+			pwm {
+				compatible = "st,stm32-pwm";
+				status = "disabled";
+			};
+
+			timer {
+				compatible = "st,stm32-timer-trigger";
+				reg = <4>;
+				status = "disabled";
+			};
+		};
+
+		timers6: timers@40001000 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			compatible = "st,stm32-timers";
+			reg = <0x40001000 0x400>;
+			clocks = <&rcc 0 132>;
+			clock-names = "clk_int";
+			status = "disabled";
+
+			timer {
+				compatible = "st,stm32-timer-trigger";
+				reg = <5>;
+				status = "disabled";
+			};
+		};
+
+		timers7: timers@40001400 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			compatible = "st,stm32-timers";
+			reg = <0x40001400 0x400>;
+			clocks = <&rcc 0 133>;
+			clock-names = "clk_int";
+			status = "disabled";
+
+			timer {
+				compatible = "st,stm32-timer-trigger";
+				reg = <6>;
+				status = "disabled";
+			};
+		};
+
+		timers12: timers@40001800 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			compatible = "st,stm32-timers";
+			reg = <0x40001800 0x400>;
+			clocks = <&rcc 0 134>;
+			clock-names = "clk_int";
+			status = "disabled";
+
+			pwm {
+				compatible = "st,stm32-pwm";
+				status = "disabled";
+			};
+
+			timer {
+				compatible = "st,stm32-timer-trigger";
+				reg = <9>;
+				status = "disabled";
+			};
+		};
+
+		timers13: timers@40001C00 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			compatible = "st,stm32-timers";
+			reg = <0x40001C00 0x400>;
+			clocks = <&rcc 0 135>;
+			clock-names = "clk_int";
+			status = "disabled";
+
+			pwm {
+				compatible = "st,stm32-pwm";
+				status = "disabled";
+			};
+		};
+
+		timers14: timers@40002000 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			compatible = "st,stm32-timers";
+			reg = <0x40002000 0x400>;
+			clocks = <&rcc 0 136>;
+			clock-names = "clk_int";
+			status = "disabled";
+
+			pwm {
+				compatible = "st,stm32-pwm";
+				status = "disabled";
+			};
+		};
+
+		timers1: timers@40010000 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			compatible = "st,stm32-timers";
+			reg = <0x40010000 0x400>;
+			clocks = <&rcc 0 160>;
+			clock-names = "clk_int";
+			status = "disabled";
+
+			pwm {
+				compatible = "st,stm32-pwm";
+				status = "disabled";
+			};
+
+			timer {
+				compatible = "st,stm32-timer-trigger";
+				reg = <0>;
+				status = "disabled";
+			};
+		};
+
+		timers8: timers@40010400 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			compatible = "st,stm32-timers";
+			reg = <0x40010400 0x400>;
+			clocks = <&rcc 0 161>;
+			clock-names = "clk_int";
+			status = "disabled";
+
+			pwm {
+				compatible = "st,stm32-pwm";
+				status = "disabled";
+			};
+
+			timer {
+				compatible = "st,stm32-timer-trigger";
+				reg = <7>;
+				status = "disabled";
+			};
+		};
+
+		timers9: timers@40014000 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			compatible = "st,stm32-timers";
+			reg = <0x40014000 0x400>;
+			clocks = <&rcc 0 176>;
+			clock-names = "clk_int";
+			status = "disabled";
+
+			pwm {
+				compatible = "st,stm32-pwm";
+				status = "disabled";
+			};
+
+			timer {
+				compatible = "st,stm32-timer-trigger";
+				reg = <8>;
+				status = "disabled";
+			};
+		};
+
+		timers10: timers@40014400 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			compatible = "st,stm32-timers";
+			reg = <0x40014400 0x400>;
+			clocks = <&rcc 0 177>;
+			clock-names = "clk_int";
+			status = "disabled";
+
+			pwm {
+				compatible = "st,stm32-pwm";
+				status = "disabled";
+			};
+		};
+
+		timers11: timers@40014800 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			compatible = "st,stm32-timers";
+			reg = <0x40014800 0x400>;
+			clocks = <&rcc 0 178>;
+			clock-names = "clk_int";
+			status = "disabled";
+
+			pwm {
+				compatible = "st,stm32-pwm";
+				status = "disabled";
+			};
+		};
 	};
 };
 
-- 
1.9.1

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#1539382 — [PATCH v6 4/8] PWM: add PWM driver for STM32 plaftorm

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 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 | 434 ++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 444 insertions(+)
 create mode 100644 drivers/pwm/pwm-stm32.c

diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig
index bf01288..f769b2a 100644
--- a/drivers/pwm/Kconfig
+++ b/drivers/pwm/Kconfig
@@ -388,6 +388,15 @@ 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 (ARCH_STM32 && OF && 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 1194c54..5aa9308 100644
--- a/drivers/pwm/Makefile
+++ b/drivers/pwm/Makefile
@@ -37,6 +37,7 @@ 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..fcf0a78
--- /dev/null
+++ b/drivers/pwm/pwm-stm32.c
@@ -0,0 +1,434 @@
+/*
+ * 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/platform_device.h>
+#include <linux/pwm.h>
+#include <linux/of.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;
+	unsigned int caps;
+	unsigned int npwm;
+	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, struct pwm_device *pwm,
+		      u32 value)
+{
+	switch (pwm->hwpwm) {
+	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 pwm_chip *chip, struct pwm_device *pwm,
+			    int duty_ns, int period_ns)
+{
+	struct stm32_pwm *priv = to_stm32_pwm_dev(chip);
+	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) {
+		dev_err(chip->dev, "prescaler exceeds the maximum value\n");
+		return -EINVAL;
+	}
+
+	/*
+	 * All channels share the same prescaler and counter so when two
+	 * channels are active at the same we can't change them
+	 */
+	if (active_channels(priv) & ~(1 << pwm->hwpwm * 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, pwm, dty);
+
+	/* Configure output mode */
+	shift = (pwm->hwpwm & 0x1) * CCMR_CHANNEL_SHIFT;
+	ccmr = (TIM_CCMR_PE | TIM_CCMR_M1) << shift;
+	mask = CCMR_CHANNEL_MASK << shift;
+
+	if (pwm->hwpwm < 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 pwm_chip *chip, struct pwm_device *pwm,
+				  enum pwm_polarity polarity)
+{
+	u32 mask;
+	struct stm32_pwm *priv = to_stm32_pwm_dev(chip);
+
+	mask = TIM_CCER_CC1P << (pwm->hwpwm * 4);
+	if (priv->have_complementary_output)
+		mask |= TIM_CCER_CC1NP << (pwm->hwpwm * 4);
+
+	regmap_update_bits(priv->regmap, TIM_CCER, mask,
+			   polarity == PWM_POLARITY_NORMAL ? 0 : mask);
+
+	return 0;
+}
+
+static int stm32_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	u32 mask;
+	struct stm32_pwm *priv = to_stm32_pwm_dev(chip);
+
+	clk_enable(priv->clk);
+
+	/* Enable channel */
+	mask = TIM_CCER_CC1E << (pwm->hwpwm * 4);
+	if (priv->have_complementary_output)
+		mask |= TIM_CCER_CC1NE << (pwm->hwpwm * 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 pwm_chip *chip, struct pwm_device *pwm)
+{
+	u32 mask;
+	struct stm32_pwm *priv = to_stm32_pwm_dev(chip);
+
+	/* Disable channel */
+	mask = TIM_CCER_CC1E << (pwm->hwpwm * 4);
+	if (priv->have_complementary_output)
+		mask |= TIM_CCER_CC1NE << (pwm->hwpwm * 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;
+	int ret;
+
+	pwm_get_state(pwm, &curstate);
+	enabled = curstate.enabled;
+
+	if (enabled && !state->enabled) {
+		stm32_pwm_disable(chip, pwm);
+		return 0;
+	}
+
+	if (state->polarity != curstate.polarity && enabled)
+		stm32_pwm_set_polarity(chip, pwm, state->polarity);
+
+	ret = stm32_pwm_config(chip, pwm, state->duty_cycle, state->period);
+	if (ret)
+		return ret;
+
+	if (!enabled && state->enabled)
+		ret = stm32_pwm_enable(chip, pwm);
+
+	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 level, int filter)
+{
+	u32 bdtr = TIM_BDTR_BKE;
+
+	if (level)
+		bdtr |= TIM_BDTR_BKP;
+
+	bdtr |= (filter & TIM_BDTR_BKF_MASK) << TIM_BDTR_BKF_SHIFT;
+
+	regmap_update_bits(priv->regmap,
+			   TIM_BDTR, TIM_BDTR_BKE | TIM_BDTR_BKP | TIM_BDTR_BKF,
+			   bdtr);
+
+	regmap_read(priv->regmap, TIM_BDTR, &bdtr);
+
+	return (bdtr & TIM_BDTR_BKE) ? 0 : -EINVAL;
+}
+
+static int stm32_pwm_set_breakinput2(struct stm32_pwm *priv,
+				     int level, int filter)
+{
+	u32 bdtr = TIM_BDTR_BK2E;
+
+	if (level)
+		bdtr |= TIM_BDTR_BK2P;
+
+	bdtr |= (filter & TIM_BDTR_BKF_MASK) << TIM_BDTR_BK2F_SHIFT;
+
+	regmap_update_bits(priv->regmap,
+			   TIM_BDTR, TIM_BDTR_BK2E |
+			   TIM_BDTR_BK2P |
+			   TIM_BDTR_BK2F,
+			   bdtr);
+
+	regmap_read(priv->regmap, TIM_BDTR, &bdtr);
+
+	return (bdtr & TIM_BDTR_BK2E) ? 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",
+					 &breakinput[0].index, array_size);
+	if (ret)
+		return ret;
+
+	for (i = 0; i < nb && !ret; i++) {
+		switch (breakinput[i].index) {
+		case 0:
+		{
+			ret = stm32_pwm_set_breakinput(priv,
+						       breakinput[i].level,
+						       breakinput[i].filter);
+			break;
+		}
+		case 1:
+		{
+			ret = stm32_pwm_set_breakinput2(priv,
+							breakinput[i].level,
+							breakinput[i].filter);
+
+			break;
+		}
+		default:
+		{
+			ret = -EINVAL;
+			break;
+		}
+		}
+	}
+
+	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_CCXE, 0);
+
+	priv->have_complementary_output = (ccer != 0);
+}
+
+static void stm32_pwm_detect_channels(struct stm32_pwm *priv)
+{
+	u32 ccer;
+
+	/*
+	 * 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)
+		priv->npwm++;
+
+	if (ccer & TIM_CCER_CC2E)
+		priv->npwm++;
+
+	if (ccer & TIM_CCER_CC3E)
+		priv->npwm++;
+
+	if (ccer & TIM_CCER_CC4E)
+		priv->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);
+	stm32_pwm_detect_channels(priv);
+
+	priv->chip.base = -1;
+	priv->chip.dev = dev;
+	priv->chip.ops = &stm32pwm_ops;
+	priv->chip.npwm = priv->npwm;
+
+	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->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");
-- 
1.9.1

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#1539383 — [PATCH v6 1/8] MFD: add bindings for STM32 Timers driver

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>
---
 .../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..b30868e
--- /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 "clk_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 {
+			compatible = "st,stm32-timer-trigger";
+			reg = <0>;
+		};
+	};
-- 
1.9.1

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#1539384 — [PATCH v6 8/8] ARM: dts: stm32: Enable pw1 and pwm3 for stm32f469-disco

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..0750a71 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 {
+		status = "okay";
+	};
+};
+
+&timers3 {
+	status = "okay";
+
+	pwm {
+		pinctrl-0 = <&pwm3_pins>;
+		pinctrl-names = "default";
+		status = "okay";
+	};
+
+	timer {
+		status = "okay";
+	};
+};
-- 
1.9.1

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