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>

1 files changed, 184 insertions, 0 deletions

diff --git a/drivers/pwm/pwm-twl6030.c b/drivers/pwm/pwm-twl6030.c
new file mode 100644
index 000000000000..8e6387864ca2
--- /dev/null
+++ b/drivers/pwm/pwm-twl6030.c
@@ -0,0 +1,184 @@
+/*
+ * twl6030_pwm.c
+ * Driver for PHOENIX (TWL6030) Pulse Width Modulator
+ *
+ * Copyright (C) 2010 Texas Instruments
+ * Author: Hemanth V <hemanthv@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pwm.h>
+#include <linux/i2c/twl.h>
+#include <linux/slab.h>
+
+#define LED_PWM_CTRL1	0xF4
+#define LED_PWM_CTRL2	0xF5
+
+/* Max value for CTRL1 register */
+#define PWM_CTRL1_MAX	255
+
+/* Pull down disable */
+#define PWM_CTRL2_DIS_PD	(1 << 6)
+
+/* Current control 2.5 milli Amps */
+#define PWM_CTRL2_CURR_02	(2 << 4)
+
+/* LED supply source */
+#define PWM_CTRL2_SRC_VAC	(1 << 2)
+
+/* LED modes */
+#define PWM_CTRL2_MODE_HW	(0 << 0)
+#define PWM_CTRL2_MODE_SW	(1 << 0)
+#define PWM_CTRL2_MODE_DIS	(2 << 0)
+
+#define PWM_CTRL2_MODE_MASK	0x3
+
+struct twl6030_pwm_chip {
+	struct pwm_chip chip;
+};
+
+static int twl6030_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	int ret;
+	u8 val;
+
+	/* Configure PWM */
+	val = PWM_CTRL2_DIS_PD | PWM_CTRL2_CURR_02 | PWM_CTRL2_SRC_VAC |
+	      PWM_CTRL2_MODE_HW;
+
+	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;
+	}
+
+	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;
+}
+
+static int twl6030_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	int ret;
+	u8 val;
+
+	ret = twl_i2c_read_u8(TWL6030_MODULE_ID1, &val, LED_PWM_CTRL2);
+	if (ret < 0) {
+		dev_err(chip->dev, "%s: Failed to enable PWM, Error %d\n",
+			pwm->label, ret);
+		return ret;
+	}
+
+	/* Change mode to software control */
+	val &= ~PWM_CTRL2_MODE_MASK;
+	val |= PWM_CTRL2_MODE_SW;
+
+	ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, LED_PWM_CTRL2);
+	if (ret < 0) {
+		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;
+}
+
+static void twl6030_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	int ret;
+	u8 val;
+
+	ret = twl_i2c_read_u8(TWL6030_MODULE_ID1, &val, LED_PWM_CTRL2);
+	if (ret < 0) {
+		dev_err(chip->dev, "%s: Failed to disable PWM, Error %d\n",
+			pwm->label, ret);
+		return;
+	}
+
+	val &= ~PWM_CTRL2_MODE_MASK;
+	val |= PWM_CTRL2_MODE_HW;
+
+	ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, LED_PWM_CTRL2);
+	if (ret < 0) {
+		dev_err(chip->dev, "%s: Failed to disable PWM, Error %d\n",
+			pwm->label, ret);
+	}
+}
+
+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)
+{
+	struct twl6030_pwm_chip *twl6030;
+	int ret;
+
+	twl6030 = devm_kzalloc(&pdev->dev, sizeof(*twl6030), GFP_KERNEL);
+	if (!twl6030)
+		return -ENOMEM;
+
+	twl6030->chip.dev = &pdev->dev;
+	twl6030->chip.ops = &twl6030_pwm_ops;
+	twl6030->chip.base = -1;
+	twl6030->chip.npwm = 1;
+
+	ret = pwmchip_add(&twl6030->chip);
+	if (ret < 0)
+		return ret;
+
+	platform_set_drvdata(pdev, twl6030);
+
+	return 0;
+}
+
+static int twl6030_pwm_remove(struct platform_device *pdev)
+{
+	struct twl6030_pwm_chip *twl6030 = platform_get_drvdata(pdev);
+
+	return pwmchip_remove(&twl6030->chip);
+}
+
+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");