[PATCH 23/26] mfd: ab8500-pwm: Enable support for AB8505 PWMLED blink
Lee Jones
lee.jones at linaro.org
Tue Jan 15 07:56:03 EST 2013
From: Naga Radhesh <naga.radheshy at stericsson.com>
Enable support for PWM OUT LED blinking for AB8505. Instead of
having 3 pwm instances from ab8500 core file add it as platform data.
Signed-off-by: Lee Jones <lee.jones at linaro.org>
Signed-off-by: Naga Radhesh <naga.radheshy at stericsson.com>
Reviewed-by: Arun MURTHY <arun.murthy at stericsson.com>
Reviewed-by: Srinidhi KASAGAR <srinidhi.kasagar at stericsson.com>
---
drivers/mfd/ab8500-core.c | 10 --
drivers/misc/ab8500-pwm.c | 282 ++++++++++++++++++++++++++++++++++++
include/linux/mfd/ab8500/pwmleds.h | 20 +++
include/linux/mfd/abx500/ab8500.h | 2 +
4 files changed, 304 insertions(+), 10 deletions(-)
create mode 100644 drivers/misc/ab8500-pwm.c
create mode 100644 include/linux/mfd/ab8500/pwmleds.h
diff --git a/drivers/mfd/ab8500-core.c b/drivers/mfd/ab8500-core.c
index 580adf3..c758469 100644
--- a/drivers/mfd/ab8500-core.c
+++ b/drivers/mfd/ab8500-core.c
@@ -1015,16 +1015,6 @@ static struct mfd_cell __devinitdata abx500_common_devs[] = {
.id = 1,
},
{
- .name = "ab8500-pwm",
- .of_compatible = "stericsson,ab8500-pwm",
- .id = 2,
- },
- {
- .name = "ab8500-pwm",
- .of_compatible = "stericsson,ab8500-pwm",
- .id = 3,
- },
- {
.name = "ab8500-leds",
.of_compatible = "stericsson,ab8500-leds",
},
diff --git a/drivers/misc/ab8500-pwm.c b/drivers/misc/ab8500-pwm.c
new file mode 100644
index 0000000..d7a6276
--- /dev/null
+++ b/drivers/misc/ab8500-pwm.c
@@ -0,0 +1,282 @@
+/*
+ * Copyright (C) ST-Ericsson SA 2010
+ *
+ * Author: Arun R Murthy <arun.murthy at stericsson.com>
+ * License terms: GNU General Public License (GPL) version 2
+ */
+#include <linux/err.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/pwm.h>
+#include <linux/clk.h>
+#include <linux/mfd/abx500.h>
+#include <linux/mfd/abx500/ab8500.h>
+#include <linux/module.h>
+#include <linux/mfd/ab8500/pwmleds.h>
+/*
+ * PWM Out generators
+ * Bank: 0x10
+ */
+#define AB8500_PWM_OUT_CTRL1_REG 0x60
+#define AB8500_PWM_OUT_CTRL2_REG 0x61
+#define AB8500_PWM_OUT_CTRL7_REG 0x66
+#define AB8505_PWM_OUT_BLINK_CTRL1_REG 0x68
+#define AB8505_PWM_OUT_BLINK_CTRL4_REG 0x6B
+#define AB8505_PWM_OUT_BLINK_CTRL_DUTYBIT 4
+#define AB8505_PWM_OUT_BLINK_DUTYMASK (0x0F << AB8505_PWM_OUT_BLINK_CTRL_DUTYBIT)
+
+
+/* backlight driver constants */
+#define ENABLE_PWM 1
+#define DISABLE_PWM 0
+
+struct pwm_device {
+ struct device *dev;
+ struct list_head node;
+ struct clk *clk;
+ const char *label;
+ unsigned int pwm_id;
+ unsigned int blink_en;
+ struct ab8500 *parent;
+ bool clk_enabled;
+};
+
+static LIST_HEAD(pwm_list);
+
+int pwm_config_blink(struct pwm_device *pwm, int duty_ns, int period_ns)
+{
+ int ret;
+ unsigned int value;
+ u8 reg;
+ if ((!is_ab8505(pwm->parent)) || (!pwm->blink_en)) {
+ dev_err(pwm->dev, "setting blinking for this "
+ "device not supported\n");
+ return -EINVAL;
+ }
+ /*
+ * get the period value that is to be written to
+ * AB8500_PWM_OUT_BLINK_CTRL1 REGS[0:2]
+ */
+ value = period_ns & 0x07;
+ /*
+ * get blink duty value to be written to
+ * AB8500_PWM_OUT_BLINK_CTRL REGS[7:4]
+ */
+ value |= ((duty_ns << AB8505_PWM_OUT_BLINK_CTRL_DUTYBIT) &
+ AB8505_PWM_OUT_BLINK_DUTYMASK);
+
+ reg = AB8505_PWM_OUT_BLINK_CTRL1_REG + (pwm->pwm_id - 1);
+
+ ret = abx500_set_register_interruptible(pwm->dev, AB8500_MISC,
+ reg, (u8)value);
+ if (ret < 0)
+ dev_err(pwm->dev, "%s: Failed to config PWM blink,Error %d\n",
+ pwm->label, ret);
+ return ret;
+}
+
+int pwm_blink_ctrl(struct pwm_device *pwm , int enable)
+{
+ int ret;
+
+ if ((!is_ab8505(pwm->parent)) || (!pwm->blink_en)) {
+ dev_err(pwm->dev, "setting blinking for this "
+ "device not supported\n");
+ return -EINVAL;
+ }
+ /*
+ * Enable/disable blinking feature for corresponding PWMOUT
+ * channel depending on value of enable.
+ */
+ ret = abx500_mask_and_set_register_interruptible(pwm->dev,
+ AB8500_MISC, AB8505_PWM_OUT_BLINK_CTRL4_REG,
+ 1 << (pwm->pwm_id-1), enable << (pwm->pwm_id-1));
+ if (ret < 0)
+ dev_err(pwm->dev, "%s: Failed to control PWM blink,Error %d\n",
+ pwm->label, ret);
+ return ret;
+}
+
+int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns)
+{
+ int ret = 0;
+ unsigned int higher_val, lower_val;
+ u8 reg;
+
+ /*
+ * get the first 8 bits that are be written to
+ * AB8500_PWM_OUT_CTRL1_REG[0:7]
+ */
+ lower_val = duty_ns & 0x00FF;
+ /*
+ * get bits [9:10] that are to be written to
+ * AB8500_PWM_OUT_CTRL2_REG[0:1]
+ */
+ higher_val = ((duty_ns & 0x0300) >> 8);
+
+ reg = AB8500_PWM_OUT_CTRL1_REG + ((pwm->pwm_id - 1) * 2);
+
+ ret = abx500_set_register_interruptible(pwm->dev, AB8500_MISC,
+ reg, (u8)lower_val);
+ if (ret < 0)
+ return ret;
+ ret = abx500_set_register_interruptible(pwm->dev, AB8500_MISC,
+ (reg + 1), (u8)higher_val);
+
+ return ret;
+}
+EXPORT_SYMBOL(pwm_config);
+
+int pwm_enable(struct pwm_device *pwm)
+{
+ int ret;
+
+ if (!pwm->clk_enabled) {
+ ret = clk_enable(pwm->clk);
+ if (ret < 0) {
+ dev_err(pwm->dev, "failed to enable clock\n");
+ return ret;
+ }
+ pwm->clk_enabled = true;
+ }
+ ret = abx500_mask_and_set_register_interruptible(pwm->dev,
+ AB8500_MISC, AB8500_PWM_OUT_CTRL7_REG,
+ 1 << (pwm->pwm_id-1), 1 << (pwm->pwm_id-1));
+ if (ret < 0)
+ dev_err(pwm->dev, "%s: Failed to enable PWM, Error %d\n",
+ pwm->label, ret);
+ return ret;
+}
+EXPORT_SYMBOL(pwm_enable);
+
+void pwm_disable(struct pwm_device *pwm)
+{
+ int ret;
+
+ ret = abx500_mask_and_set_register_interruptible(pwm->dev,
+ AB8500_MISC, AB8500_PWM_OUT_CTRL7_REG,
+ 1 << (pwm->pwm_id-1), DISABLE_PWM);
+ /*
+ * Workaround to set PWM in disable.
+ * If enable bit is not toggled the PWM might output 50/50 duty cycle
+ * even though it should be disabled
+ */
+ ret &= abx500_mask_and_set_register_interruptible(pwm->dev,
+ AB8500_MISC, AB8500_PWM_OUT_CTRL7_REG,
+ 1 << (pwm->pwm_id-1),
+ ENABLE_PWM << (pwm->pwm_id-1));
+ ret &= abx500_mask_and_set_register_interruptible(pwm->dev,
+ AB8500_MISC, AB8500_PWM_OUT_CTRL7_REG,
+ 1 << (pwm->pwm_id-1), DISABLE_PWM);
+
+ if (ret < 0)
+ dev_err(pwm->dev, "%s: Failed to disable PWM, Error %d\n",
+ pwm->label, ret);
+ if (pwm->clk_enabled) {
+ clk_disable(pwm->clk);
+ pwm->clk_enabled = false;
+ }
+
+ return;
+}
+EXPORT_SYMBOL(pwm_disable);
+
+struct pwm_device *pwm_request(int pwm_id, const char *label)
+{
+ struct pwm_device *pwm;
+ list_for_each_entry(pwm, &pwm_list, node) {
+ if (pwm->pwm_id == pwm_id) {
+ pwm->label = label;
+ pwm->pwm_id = pwm_id;
+ return pwm;
+ }
+ }
+
+ return ERR_PTR(-ENOENT);
+}
+EXPORT_SYMBOL(pwm_request);
+
+void pwm_free(struct pwm_device *pwm)
+{
+ pwm_disable(pwm);
+}
+EXPORT_SYMBOL(pwm_free);
+
+static int __devinit ab8500_pwm_probe(struct platform_device *pdev)
+{
+ struct ab8500 *parent = dev_get_drvdata(pdev->dev.parent);
+ struct ab8500_platform_data *plat = dev_get_platdata(parent->dev);
+ struct ab8500_pwmled_platform_data *pdata = plat->pwmled;
+ struct pwm_device *pwm;
+ int ret = 0 , i;
+
+ /*
+ * Nothing to be done in probe, this is required to get the
+ * device which is required for ab8500 read and write
+ */
+ pwm = kzalloc(((sizeof(struct pwm_device)) * pdata->num_pwm),
+ GFP_KERNEL);
+ if (pwm == NULL) {
+ dev_err(&pdev->dev, "failed to allocate memory\n");
+ return -ENOMEM;
+ }
+ for (i = 0; i < pdata->num_pwm; i++) {
+ pwm[i].dev = &pdev->dev;
+ pwm[i].parent = parent;
+ pwm[i].blink_en = pdata->leds[i].blink_en;
+ pwm[i].pwm_id = pdata->leds[i].pwm_id;
+ list_add_tail(&pwm[i].node, &pwm_list);
+ }
+ pwm->clk = clk_get(pwm->dev, NULL);
+ if (IS_ERR(pwm->clk)) {
+ dev_err(pwm->dev, "clock request failed\n");
+ ret = PTR_ERR(pwm->clk);
+ goto fail;
+ }
+ platform_set_drvdata(pdev, pwm);
+ pwm->clk_enabled = false;
+ dev_dbg(pwm->dev, "pwm probe successful\n");
+ return ret;
+
+fail:
+ list_del(&pwm->node);
+ kfree(pwm);
+ return ret;
+}
+
+static int __devexit ab8500_pwm_remove(struct platform_device *pdev)
+{
+ struct pwm_device *pwm = platform_get_drvdata(pdev);
+
+ list_del(&pwm->node);
+ clk_put(pwm->clk);
+ dev_dbg(&pdev->dev, "pwm driver removed\n");
+ kfree(pwm);
+ return 0;
+}
+
+static struct platform_driver ab8500_pwm_driver = {
+ .driver = {
+ .name = "ab8500-pwm",
+ .owner = THIS_MODULE,
+ },
+ .probe = ab8500_pwm_probe,
+ .remove = __devexit_p(ab8500_pwm_remove),
+};
+
+static int __init ab8500_pwm_init(void)
+{
+ return platform_driver_register(&ab8500_pwm_driver);
+}
+
+static void __exit ab8500_pwm_exit(void)
+{
+ platform_driver_unregister(&ab8500_pwm_driver);
+}
+
+subsys_initcall(ab8500_pwm_init);
+module_exit(ab8500_pwm_exit);
+MODULE_AUTHOR("Arun MURTHY <arun.murthy at stericsson.com>");
+MODULE_DESCRIPTION("AB8500 Pulse Width Modulation Driver");
+MODULE_ALIAS("platform:ab8500-pwm");
+MODULE_LICENSE("GPL v2");
diff --git a/include/linux/mfd/ab8500/pwmleds.h b/include/linux/mfd/ab8500/pwmleds.h
new file mode 100644
index 0000000..e316582
--- /dev/null
+++ b/include/linux/mfd/ab8500/pwmleds.h
@@ -0,0 +1,20 @@
+/*
+ * Copyright ST-Ericsson 2012.
+ *
+ * Author: Naga Radhesh <naga.radheshy at stericsson.com>
+ * Licensed under GPLv2.
+ */
+#ifndef _AB8500_PWMLED_H
+#define _AB8500_PWMLED_H
+
+struct ab8500_led_pwm {
+ int pwm_id;
+ int blink_en;
+};
+
+struct ab8500_pwmled_platform_data {
+ int num_pwm;
+ struct ab8500_led_pwm *leds;
+};
+
+#endif
diff --git a/include/linux/mfd/abx500/ab8500.h b/include/linux/mfd/abx500/ab8500.h
index 83de910..62cbe65 100644
--- a/include/linux/mfd/abx500/ab8500.h
+++ b/include/linux/mfd/abx500/ab8500.h
@@ -281,6 +281,7 @@ struct ab8500_sysctrl_platform_data;
* @regulator_reg_init: regulator init registers
* @num_regulator: number of regulators
* @regulator: machine-specific constraints for regulators
+ * @pwmled: machine-specific pwmled data
*/
struct ab8500_platform_data {
int irq_base;
@@ -293,6 +294,7 @@ struct ab8500_platform_data {
struct ab8500_gpio_platform_data *gpio;
struct ab8500_codec_platform_data *codec;
struct ab8500_sysctrl_platform_data *sysctrl;
+ struct ab8500_pwmled_platform_data *pwmled;
};
extern int __devinit ab8500_init(struct ab8500 *ab8500,
--
1.7.9.5
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