[PATCH v2 3/3] pwm: Add Ingenic JZ4740 support

From: Thierry Reding
Date: Mon Sep 10 2012 - 08:05:53 EST


This commit moves the driver to drivers/pwm and converts it to the new
PWM framework.

Signed-off-by: Thierry Reding <thierry.reding@xxxxxxxxxxxxxxxxx>
---
Changes in v2:
- remove PWM core hunk that slipped in by mistake
- change pwm-beeper platform data back to 4
- refer to timer.h by full path
- register PWMs 0 and 1 but reserve them for system tasks
- replace printk by dev_err now that a proper device is available
- use jz4740_pwm_{enable,disable}() instead of pwm_{enable,disable}()
internally
- make THIS_MODULE the owner of jz4740_pwm_ops and jz4740_pwm_driver
- add __devinit and __devexit annotations to jz4740_pwm_probe() and
jz4740_pwm_remove() respectively
- add MODULE_AUTHOR(), MODULE_DESCRIPTION(), MODULE_ALIAS() and
MODULE_LICENSE()

arch/mips/include/asm/mach-jz4740/platform.h | 1 +
arch/mips/jz4740/Kconfig | 3 -
arch/mips/jz4740/Makefile | 2 +-
arch/mips/jz4740/board-qi_lb60.c | 1 +
arch/mips/jz4740/platform.c | 6 +
arch/mips/jz4740/pwm.c | 177 ---------------------
drivers/pwm/Kconfig | 12 +-
drivers/pwm/Makefile | 1 +
drivers/pwm/pwm-jz4740.c | 221 +++++++++++++++++++++++++++
9 files changed, 242 insertions(+), 182 deletions(-)
delete mode 100644 arch/mips/jz4740/pwm.c
create mode 100644 drivers/pwm/pwm-jz4740.c

diff --git a/arch/mips/include/asm/mach-jz4740/platform.h b/arch/mips/include/asm/mach-jz4740/platform.h
index 564ab81..163e81d 100644
--- a/arch/mips/include/asm/mach-jz4740/platform.h
+++ b/arch/mips/include/asm/mach-jz4740/platform.h
@@ -31,6 +31,7 @@ extern struct platform_device jz4740_pcm_device;
extern struct platform_device jz4740_codec_device;
extern struct platform_device jz4740_adc_device;
extern struct platform_device jz4740_wdt_device;
+extern struct platform_device jz4740_pwm_device;

void jz4740_serial_device_register(void);

diff --git a/arch/mips/jz4740/Kconfig b/arch/mips/jz4740/Kconfig
index 3e7141f..4689030 100644
--- a/arch/mips/jz4740/Kconfig
+++ b/arch/mips/jz4740/Kconfig
@@ -7,6 +7,3 @@ config JZ4740_QI_LB60
bool "Qi Hardware Ben NanoNote"

endchoice
-
-config HAVE_PWM
- bool
diff --git a/arch/mips/jz4740/Makefile b/arch/mips/jz4740/Makefile
index e44abea..63bad0e 100644
--- a/arch/mips/jz4740/Makefile
+++ b/arch/mips/jz4740/Makefile
@@ -5,7 +5,7 @@
# Object file lists.

obj-y += prom.o irq.o time.o reset.o setup.o dma.o \
- gpio.o clock.o platform.o timer.o pwm.o serial.o
+ gpio.o clock.o platform.o timer.o serial.o

obj-$(CONFIG_DEBUG_FS) += clock-debugfs.o

diff --git a/arch/mips/jz4740/board-qi_lb60.c b/arch/mips/jz4740/board-qi_lb60.c
index 9a3d9de..43d964d 100644
--- a/arch/mips/jz4740/board-qi_lb60.c
+++ b/arch/mips/jz4740/board-qi_lb60.c
@@ -437,6 +437,7 @@ static struct platform_device *jz_platform_devices[] __initdata = {
&jz4740_codec_device,
&jz4740_rtc_device,
&jz4740_adc_device,
+ &jz4740_pwm_device,
&qi_lb60_gpio_keys,
&qi_lb60_pwm_beeper,
&qi_lb60_charger_device,
diff --git a/arch/mips/jz4740/platform.c b/arch/mips/jz4740/platform.c
index e342ed4..6d14dcd 100644
--- a/arch/mips/jz4740/platform.c
+++ b/arch/mips/jz4740/platform.c
@@ -323,3 +323,9 @@ struct platform_device jz4740_wdt_device = {
.num_resources = ARRAY_SIZE(jz4740_wdt_resources),
.resource = jz4740_wdt_resources,
};
+
+/* PWM */
+struct platform_device jz4740_pwm_device = {
+ .name = "jz4740-pwm",
+ .id = -1,
+};
diff --git a/arch/mips/jz4740/pwm.c b/arch/mips/jz4740/pwm.c
deleted file mode 100644
index a26a6fa..0000000
--- a/arch/mips/jz4740/pwm.c
+++ /dev/null
@@ -1,177 +0,0 @@
-/*
- * Copyright (C) 2010, Lars-Peter Clausen <lars@xxxxxxxxxx>
- * JZ4740 platform PWM support
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License as published by the
- * Free Software Foundation; either version 2 of the License, or (at your
- * option) any later version.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write to the Free Software Foundation, Inc.,
- * 675 Mass Ave, Cambridge, MA 02139, USA.
- *
- */
-
-#include <linux/kernel.h>
-
-#include <linux/clk.h>
-#include <linux/err.h>
-#include <linux/pwm.h>
-#include <linux/gpio.h>
-
-#include <asm/mach-jz4740/gpio.h>
-#include "timer.h"
-
-static struct clk *jz4740_pwm_clk;
-
-DEFINE_MUTEX(jz4740_pwm_mutex);
-
-struct pwm_device {
- unsigned int id;
- unsigned int gpio;
- bool used;
-};
-
-static struct pwm_device jz4740_pwm_list[] = {
- { 2, JZ_GPIO_PWM2, false },
- { 3, JZ_GPIO_PWM3, false },
- { 4, JZ_GPIO_PWM4, false },
- { 5, JZ_GPIO_PWM5, false },
- { 6, JZ_GPIO_PWM6, false },
- { 7, JZ_GPIO_PWM7, false },
-};
-
-struct pwm_device *pwm_request(int id, const char *label)
-{
- int ret = 0;
- struct pwm_device *pwm;
-
- if (id < 2 || id > 7 || !jz4740_pwm_clk)
- return ERR_PTR(-ENODEV);
-
- mutex_lock(&jz4740_pwm_mutex);
-
- pwm = &jz4740_pwm_list[id - 2];
- if (pwm->used)
- ret = -EBUSY;
- else
- pwm->used = true;
-
- mutex_unlock(&jz4740_pwm_mutex);
-
- if (ret)
- return ERR_PTR(ret);
-
- ret = gpio_request(pwm->gpio, label);
-
- if (ret) {
- printk(KERN_ERR "Failed to request pwm gpio: %d\n", ret);
- pwm->used = false;
- return ERR_PTR(ret);
- }
-
- jz_gpio_set_function(pwm->gpio, JZ_GPIO_FUNC_PWM);
-
- jz4740_timer_start(id);
-
- return pwm;
-}
-
-void pwm_free(struct pwm_device *pwm)
-{
- pwm_disable(pwm);
- jz4740_timer_set_ctrl(pwm->id, 0);
-
- jz_gpio_set_function(pwm->gpio, JZ_GPIO_FUNC_NONE);
- gpio_free(pwm->gpio);
-
- jz4740_timer_stop(pwm->id);
-
- pwm->used = false;
-}
-
-int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns)
-{
- unsigned long long tmp;
- unsigned long period, duty;
- unsigned int prescaler = 0;
- unsigned int id = pwm->id;
- uint16_t ctrl;
- bool is_enabled;
-
- if (duty_ns < 0 || duty_ns > period_ns)
- return -EINVAL;
-
- tmp = (unsigned long long)clk_get_rate(jz4740_pwm_clk) * period_ns;
- do_div(tmp, 1000000000);
- period = tmp;
-
- while (period > 0xffff && prescaler < 6) {
- period >>= 2;
- ++prescaler;
- }
-
- if (prescaler == 6)
- return -EINVAL;
-
- tmp = (unsigned long long)period * duty_ns;
- do_div(tmp, period_ns);
- duty = period - tmp;
-
- if (duty >= period)
- duty = period - 1;
-
- is_enabled = jz4740_timer_is_enabled(id);
- if (is_enabled)
- pwm_disable(pwm);
-
- jz4740_timer_set_count(id, 0);
- jz4740_timer_set_duty(id, duty);
- jz4740_timer_set_period(id, period);
-
- ctrl = JZ_TIMER_CTRL_PRESCALER(prescaler) | JZ_TIMER_CTRL_SRC_EXT |
- JZ_TIMER_CTRL_PWM_ABBRUPT_SHUTDOWN;
-
- jz4740_timer_set_ctrl(id, ctrl);
-
- if (is_enabled)
- pwm_enable(pwm);
-
- return 0;
-}
-
-int pwm_enable(struct pwm_device *pwm)
-{
- uint32_t ctrl = jz4740_timer_get_ctrl(pwm->id);
-
- ctrl |= JZ_TIMER_CTRL_PWM_ENABLE;
- jz4740_timer_set_ctrl(pwm->id, ctrl);
- jz4740_timer_enable(pwm->id);
-
- return 0;
-}
-
-void pwm_disable(struct pwm_device *pwm)
-{
- uint32_t ctrl = jz4740_timer_get_ctrl(pwm->id);
-
- ctrl &= ~JZ_TIMER_CTRL_PWM_ENABLE;
- jz4740_timer_disable(pwm->id);
- jz4740_timer_set_ctrl(pwm->id, ctrl);
-}
-
-static int __init jz4740_pwm_init(void)
-{
- int ret = 0;
-
- jz4740_pwm_clk = clk_get(NULL, "ext");
-
- if (IS_ERR(jz4740_pwm_clk)) {
- ret = PTR_ERR(jz4740_pwm_clk);
- jz4740_pwm_clk = NULL;
- }
-
- return ret;
-}
-subsys_initcall(jz4740_pwm_init);
diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig
index 90c5c73..5c663df 100644
--- a/drivers/pwm/Kconfig
+++ b/drivers/pwm/Kconfig
@@ -1,6 +1,6 @@
menuconfig PWM
bool "Pulse-Width Modulation (PWM) Support"
- depends on !MACH_JZ4740 && !PUV3_PWM
+ depends on !PUV3_PWM
help
Generic Pulse-Width Modulation (PWM) support.

@@ -47,6 +47,16 @@ config PWM_IMX
To compile this driver as a module, choose M here: the module
will be called pwm-imx.

+config PWM_JZ4740
+ tristate "Ingenic JZ4740 PWM support"
+ depends on MACH_JZ4740
+ help
+ Generic PWM framework driver for Ingenic JZ4740 based
+ machines.
+
+ To compile this driver as a module, choose M here: the module
+ will be called pwm-jz4740.
+
config PWM_LPC32XX
tristate "LPC32XX PWM support"
depends on ARCH_LPC32XX
diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile
index e4b2c89..a1d6169 100644
--- a/drivers/pwm/Makefile
+++ b/drivers/pwm/Makefile
@@ -1,6 +1,7 @@
obj-$(CONFIG_PWM) += core.o
obj-$(CONFIG_PWM_BFIN) += pwm-bfin.o
obj-$(CONFIG_PWM_IMX) += pwm-imx.o
+obj-$(CONFIG_PWM_JZ4740) += pwm-jz4740.o
obj-$(CONFIG_PWM_LPC32XX) += pwm-lpc32xx.o
obj-$(CONFIG_PWM_MXS) += pwm-mxs.o
obj-$(CONFIG_PWM_PXA) += pwm-pxa.o
diff --git a/drivers/pwm/pwm-jz4740.c b/drivers/pwm/pwm-jz4740.c
new file mode 100644
index 0000000..10250fc
--- /dev/null
+++ b/drivers/pwm/pwm-jz4740.c
@@ -0,0 +1,221 @@
+/*
+ * Copyright (C) 2010, Lars-Peter Clausen <lars@xxxxxxxxxx>
+ * JZ4740 platform PWM support
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/gpio.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pwm.h>
+
+#include <asm/mach-jz4740/gpio.h>
+#include <asm/mach-jz4740/timer.h>
+
+#define NUM_PWM 8
+
+static const unsigned int jz4740_pwm_gpio_list[NUM_PWM] = {
+ JZ_GPIO_PWM0,
+ JZ_GPIO_PWM1,
+ JZ_GPIO_PWM2,
+ JZ_GPIO_PWM3,
+ JZ_GPIO_PWM4,
+ JZ_GPIO_PWM5,
+ JZ_GPIO_PWM6,
+ JZ_GPIO_PWM7,
+};
+
+struct jz4740_pwm_chip {
+ struct pwm_chip chip;
+ struct clk *clk;
+};
+
+static inline struct jz4740_pwm_chip *to_jz4740(struct pwm_chip *chip)
+{
+ return container_of(chip, struct jz4740_pwm_chip, chip);
+}
+
+static int jz4740_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ unsigned int gpio = jz4740_pwm_gpio_list[pwm->hwpwm];
+ int ret;
+
+ /*
+ * Timers 0 and 1 are used for system tasks, so they are unavailable
+ * for use as PWMs.
+ */
+ if (pwm->hwpwm < 2)
+ return -EBUSY;
+
+ ret = gpio_request(gpio, pwm->label);
+ if (ret) {
+ dev_err(chip->dev, "Failed to request GPIO#%u for PWM: %d\n",
+ gpio, ret);
+ return ret;
+ }
+
+ jz_gpio_set_function(gpio, JZ_GPIO_FUNC_PWM);
+
+ jz4740_timer_start(pwm->hwpwm);
+
+ return 0;
+}
+
+static void jz4740_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ unsigned int gpio = jz4740_pwm_gpio_list[pwm->hwpwm];
+
+ jz4740_timer_set_ctrl(pwm->hwpwm, 0);
+
+ jz_gpio_set_function(gpio, JZ_GPIO_FUNC_NONE);
+ gpio_free(gpio);
+
+ jz4740_timer_stop(pwm->hwpwm);
+}
+
+static int jz4740_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ uint32_t ctrl = jz4740_timer_get_ctrl(pwm->pwm);
+
+ ctrl |= JZ_TIMER_CTRL_PWM_ENABLE;
+ jz4740_timer_set_ctrl(pwm->hwpwm, ctrl);
+ jz4740_timer_enable(pwm->hwpwm);
+
+ return 0;
+}
+
+static void jz4740_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ uint32_t ctrl = jz4740_timer_get_ctrl(pwm->hwpwm);
+
+ ctrl &= ~JZ_TIMER_CTRL_PWM_ENABLE;
+ jz4740_timer_disable(pwm->hwpwm);
+ jz4740_timer_set_ctrl(pwm->hwpwm, ctrl);
+}
+
+static int jz4740_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
+ int duty_ns, int period_ns)
+{
+ struct jz4740_pwm_chip *jz4740 = to_jz4740(pwm->chip);
+ unsigned long long tmp;
+ unsigned long period, duty;
+ unsigned int prescaler = 0;
+ uint16_t ctrl;
+ bool is_enabled;
+
+ tmp = (unsigned long long)clk_get_rate(jz4740->clk) * period_ns;
+ do_div(tmp, 1000000000);
+ period = tmp;
+
+ while (period > 0xffff && prescaler < 6) {
+ period >>= 2;
+ ++prescaler;
+ }
+
+ if (prescaler == 6)
+ return -EINVAL;
+
+ tmp = (unsigned long long)period * duty_ns;
+ do_div(tmp, period_ns);
+ duty = period - tmp;
+
+ if (duty >= period)
+ duty = period - 1;
+
+ is_enabled = jz4740_timer_is_enabled(pwm->hwpwm);
+ if (is_enabled)
+ jz4740_pwm_disable(chip, pwm);
+
+ jz4740_timer_set_count(pwm->hwpwm, 0);
+ jz4740_timer_set_duty(pwm->hwpwm, duty);
+ jz4740_timer_set_period(pwm->hwpwm, period);
+
+ ctrl = JZ_TIMER_CTRL_PRESCALER(prescaler) | JZ_TIMER_CTRL_SRC_EXT |
+ JZ_TIMER_CTRL_PWM_ABBRUPT_SHUTDOWN;
+
+ jz4740_timer_set_ctrl(pwm->hwpwm, ctrl);
+
+ if (is_enabled)
+ jz4740_pwm_enable(chip, pwm);
+
+ return 0;
+}
+
+static const struct pwm_ops jz4740_pwm_ops = {
+ .request = jz4740_pwm_request,
+ .free = jz4740_pwm_free,
+ .config = jz4740_pwm_config,
+ .enable = jz4740_pwm_enable,
+ .disable = jz4740_pwm_disable,
+ .owner = THIS_MODULE,
+};
+
+static int __devinit jz4740_pwm_probe(struct platform_device *pdev)
+{
+ struct jz4740_pwm_chip *jz4740;
+ int ret;
+
+ jz4740 = devm_kzalloc(&pdev->dev, sizeof(*jz4740), GFP_KERNEL);
+ if (!jz4740)
+ return -ENOMEM;
+
+ jz4740->clk = clk_get(NULL, "ext");
+ if (IS_ERR(jz4740->clk))
+ return PTR_ERR(jz4740->clk);
+
+ jz4740->chip.dev = &pdev->dev;
+ jz4740->chip.ops = &jz4740_pwm_ops;
+ jz4740->chip.npwm = NUM_PWM;
+ jz4740->chip.base = -1;
+
+ ret = pwmchip_add(&jz4740->chip);
+ if (ret < 0) {
+ clk_put(jz4740->clk);
+ return ret;
+ }
+
+ platform_set_drvdata(pdev, jz4740);
+
+ return 0;
+}
+
+static int __devexit jz4740_pwm_remove(struct platform_device *pdev)
+{
+ struct jz4740_pwm_chip *jz4740 = platform_get_drvdata(pdev);
+ int ret;
+
+ ret = pwmchip_remove(&jz4740->chip);
+ if (ret < 0)
+ return ret;
+
+ clk_put(jz4740->clk);
+
+ return 0;
+}
+
+static struct platform_driver jz4740_pwm_driver = {
+ .driver = {
+ .name = "jz4740-pwm",
+ .owner = THIS_MODULE,
+ },
+ .probe = jz4740_pwm_probe,
+ .remove = __devexit_p(jz4740_pwm_remove),
+};
+module_platform_driver(jz4740_pwm_driver);
+
+MODULE_AUTHOR("Lars-Peter Clausen <lars@xxxxxxxxxx>");
+MODULE_DESCRIPTION("Ingenic JZ4740 PWM driver");
+MODULE_ALIAS("platform:jz4740-pwm");
+MODULE_LICENSE("GPL");
--
1.7.12

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