pwm: Move TWL6030 PWM driver to PWM framework

This commit moves the driver to drivers/pwm and converts it to the new
PWM framework. In order for this to work properly, register the PWM as
child of the multi-function TWL6030 device.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Acked-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

6 files changed, 86 insertions, 61 deletions

diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index b0d7d9b5b7d4..2143fd283a74 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -298,16 +298,6 @@ config MFD_TWL4030_AUDIO
         select MFD_CORE
         default n
 
-config TWL6030_PWM
-        tristate "TWL6030 PWM (Pulse Width Modulator) Support"
-        depends on TWL4030_CORE
-        select HAVE_PWM
-        depends on !PWM
-        default n
-        help
-          Say yes here if you want support for TWL6030 PWM.
-          This is used to control charging LED brightness.
-
 config TWL6040_CORE
         bool "Support for TWL6040 audio codec"
         depends on I2C=y && GENERIC_HARDIRQS
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index b88cdb876e15..95dfa14ad174 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -63,7 +63,6 @@ obj-$(CONFIG_TWL4030_CORE)	+= twl-core.o twl4030-irq.o twl6030-irq.o
 obj-$(CONFIG_TWL4030_MADC)      += twl4030-madc.o
 obj-$(CONFIG_TWL4030_POWER)    += twl4030-power.o
 obj-$(CONFIG_MFD_TWL4030_AUDIO) += twl4030-audio.o
-obj-$(CONFIG_TWL6030_PWM)       += twl6030-pwm.o
 obj-$(CONFIG_TWL6040_CORE)      += twl6040-core.o twl6040-irq.o
 
 obj-$(CONFIG_MFD_MC13XXX)       += mc13xxx-core.o
diff --git a/drivers/mfd/twl-core.c b/drivers/mfd/twl-core.c
index e208d88d2180..3d700129cf3e 100644
--- a/drivers/mfd/twl-core.c
+++ b/drivers/mfd/twl-core.c
@@ -670,6 +670,13 @@ add_children(struct twl4030_platform_data *pdata, unsigned irq_base,
                         return PTR_ERR(child);
         }
 
+        if (IS_ENABLED(CONFIG_PWM_TWL6030) && twl_class_is_6030()) {
+                child = add_child(TWL6030_MODULE_ID1, "twl6030-pwm", NULL, 0,
+                                  false, 0, 0);
+                if (IS_ERR(child))
+                        return PTR_ERR(child);
+        }
+
         if (IS_ENABLED(CONFIG_TWL4030_USB) && pdata->usb &&
             twl_class_is_4030()) {
 
diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig
index 8fc3808d7a3e..c7500dcdc65e 100644
--- a/drivers/pwm/Kconfig
+++ b/drivers/pwm/Kconfig
@@ -96,6 +96,15 @@ config  PWM_TIEHRPWM
           To compile this driver as a module, choose M here: the module
           will be called pwm-tiehrpwm.
 
+config PWM_TWL6030
+        tristate "TWL6030 PWM support"
+        depends on TWL4030_CORE
+        help
+          Generic PWM framework driver for TWL6030.
+
+          To compile this driver as a module, choose M here: the module
+          will be called pwm-twl6030.
+
 config PWM_VT8500
         tristate "vt8500 pwm support"
         depends on ARCH_VT8500
diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile
index e4b2c898964d..78f123dca30d 100644
--- a/drivers/pwm/Makefile
+++ b/drivers/pwm/Makefile
@@ -8,4 +8,5 @@ obj-$(CONFIG_PWM_SAMSUNG)	+= pwm-samsung.o
 obj-$(CONFIG_PWM_TEGRA)         += pwm-tegra.o
 obj-$(CONFIG_PWM_TIECAP)        += pwm-tiecap.o
 obj-$(CONFIG_PWM_TIEHRPWM)      += pwm-tiehrpwm.o
+obj-$(CONFIG_PWM_TWL6030)       += pwm-twl6030.o
 obj-$(CONFIG_PWM_VT8500)        += pwm-vt8500.o
diff --git a/drivers/mfd/twl6030-pwm.c b/drivers/pwm/pwm-twl6030.c
index e8fee147678d..8e6387864ca2 100644
--- a/drivers/mfd/twl6030-pwm.c
+++ b/drivers/pwm/pwm-twl6030.c
@@ -20,6 +20,7 @@
 
 #include <linux/module.h>
 #include <linux/platform_device.h>
+#include <linux/pwm.h>
 #include <linux/i2c/twl.h>
 #include <linux/slab.h>
 
@@ -45,40 +46,54 @@
 
 #define PWM_CTRL2_MODE_MASK     0x3
 
-struct pwm_device {
-        const char *label;
-        unsigned int pwm_id;
+struct twl6030_pwm_chip {
+        struct pwm_chip chip;
 };
 
-int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns)
+static int twl6030_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
 {
-        u8 duty_cycle;
         int ret;
+        u8 val;
 
-        if (pwm == NULL || period_ns == 0 || duty_ns > period_ns)
-                return -EINVAL;
+        /* Configure PWM */
+        val = PWM_CTRL2_DIS_PD | PWM_CTRL2_CURR_02 | PWM_CTRL2_SRC_VAC |
+              PWM_CTRL2_MODE_HW;
 
-        duty_cycle = (duty_ns * PWM_CTRL1_MAX) / period_ns;
+        ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, LED_PWM_CTRL2);
+        if (ret < 0) {
+                dev_err(chip->dev, "%s: Failed to configure PWM, Error %d\n",
+                        pwm->label, ret);
+                return ret;
+        }
 
-        ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, duty_cycle, LED_PWM_CTRL1);
+        return 0;
+}
 
+static int twl6030_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
+                              int duty_ns, int period_ns)
+{
+        u8 duty_cycle = (duty_ns * PWM_CTRL1_MAX) / period_ns;
+        int ret;
+
+        ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, duty_cycle, LED_PWM_CTRL1);
         if (ret < 0) {
                 pr_err("%s: Failed to configure PWM, Error %d\n",
                         pwm->label, ret);
                 return ret;
         }
+
         return 0;
 }
-EXPORT_SYMBOL(pwm_config);
 
-int pwm_enable(struct pwm_device *pwm)
+static int twl6030_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
 {
-        u8 val;
         int ret;
+        u8 val;
 
         ret = twl_i2c_read_u8(TWL6030_MODULE_ID1, &val, LED_PWM_CTRL2);
         if (ret < 0) {
-                pr_err("%s: Failed to enable PWM, Error %d\n", pwm->label, ret);
+                dev_err(chip->dev, "%s: Failed to enable PWM, Error %d\n",
+                        pwm->label, ret);
                 return ret;
         }
 
@@ -88,23 +103,23 @@ int pwm_enable(struct pwm_device *pwm)
 
         ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, LED_PWM_CTRL2);
         if (ret < 0) {
-                pr_err("%s: Failed to enable PWM, Error %d\n", pwm->label, ret);
+                dev_err(chip->dev, "%s: Failed to enable PWM, Error %d\n",
+                        pwm->label, ret);
                 return ret;
         }
 
         twl_i2c_read_u8(TWL6030_MODULE_ID1, &val, LED_PWM_CTRL2);
         return 0;
 }
-EXPORT_SYMBOL(pwm_enable);
 
-void pwm_disable(struct pwm_device *pwm)
+static void twl6030_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
 {
-        u8 val;
         int ret;
+        u8 val;
 
         ret = twl_i2c_read_u8(TWL6030_MODULE_ID1, &val, LED_PWM_CTRL2);
         if (ret < 0) {
-                pr_err("%s: Failed to disable PWM, Error %d\n",
+                dev_err(chip->dev, "%s: Failed to disable PWM, Error %d\n",
                         pwm->label, ret);
                 return;
         }
@@ -114,52 +129,56 @@ void pwm_disable(struct pwm_device *pwm)
 
         ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, LED_PWM_CTRL2);
         if (ret < 0) {
-                pr_err("%s: Failed to disable PWM, Error %d\n",
+                dev_err(chip->dev, "%s: Failed to disable PWM, Error %d\n",
                         pwm->label, ret);
-                return;
         }
-        return;
 }
-EXPORT_SYMBOL(pwm_disable);
 
-struct pwm_device *pwm_request(int pwm_id, const char *label)
+static const struct pwm_ops twl6030_pwm_ops = {
+        .request = twl6030_pwm_request,
+        .config = twl6030_pwm_config,
+        .enable = twl6030_pwm_enable,
+        .disable = twl6030_pwm_disable,
+};
+
+static int twl6030_pwm_probe(struct platform_device *pdev)
 {
-        u8 val;
+        struct twl6030_pwm_chip *twl6030;
         int ret;
-        struct pwm_device *pwm;
-
-        pwm = kzalloc(sizeof(struct pwm_device), GFP_KERNEL);
-        if (pwm == NULL) {
-                pr_err("%s: failed to allocate memory\n", label);
-                return NULL;
-        }
 
-        pwm->label = label;
-        pwm->pwm_id = pwm_id;
-
-        /* Configure PWM */
-        val = PWM_CTRL2_DIS_PD | PWM_CTRL2_CURR_02 | PWM_CTRL2_SRC_VAC |
-                PWM_CTRL2_MODE_HW;
+        twl6030 = devm_kzalloc(&pdev->dev, sizeof(*twl6030), GFP_KERNEL);
+        if (!twl6030)
+                return -ENOMEM;
 
-        ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, LED_PWM_CTRL2);
+        twl6030->chip.dev = &pdev->dev;
+        twl6030->chip.ops = &twl6030_pwm_ops;
+        twl6030->chip.base = -1;
+        twl6030->chip.npwm = 1;
 
-        if (ret < 0) {
-                pr_err("%s: Failed to configure PWM, Error %d\n",
-                         pwm->label, ret);
+        ret = pwmchip_add(&twl6030->chip);
+        if (ret < 0)
+                return ret;
 
-                kfree(pwm);
-                return NULL;
-        }
+        platform_set_drvdata(pdev, twl6030);
 
-        return pwm;
+        return 0;
 }
-EXPORT_SYMBOL(pwm_request);
 
-void pwm_free(struct pwm_device *pwm)
+static int twl6030_pwm_remove(struct platform_device *pdev)
 {
-        pwm_disable(pwm);
-        kfree(pwm);
+        struct twl6030_pwm_chip *twl6030 = platform_get_drvdata(pdev);
+
+        return pwmchip_remove(&twl6030->chip);
 }
-EXPORT_SYMBOL(pwm_free);
 
+static struct platform_driver twl6030_pwm_driver = {
+        .driver = {
+                .name = "twl6030-pwm",
+        },
+        .probe = twl6030_pwm_probe,
+        .remove = __devexit_p(twl6030_pwm_remove),
+};
+module_platform_driver(twl6030_pwm_driver);
+
+MODULE_ALIAS("platform:twl6030-pwm");
 MODULE_LICENSE("GPL");