Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / drivers / pwm / pwm-ab8500.c

diff --git a/kernel/drivers/pwm/pwm-ab8500.c b/kernel/drivers/pwm/pwm-ab8500.c
new file mode 100644 (file)
index 0000000..f393992
--- /dev/null
+++ b/kernel/drivers/pwm/pwm-ab8500.c
@@ -0,0 +1,143 @@
+/*
+ * Copyright (C) ST-Ericsson SA 2010
+ *
+ * Author: Arun R Murthy <arun.murthy@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/mfd/abx500.h>
+#include <linux/mfd/abx500/ab8500.h>
+#include <linux/module.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
+
+struct ab8500_pwm_chip {
+       struct pwm_chip chip;
+};
+
+static int ab8500_pwm_config(struct pwm_chip *chip, 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 + ((chip->base - 1) * 2);
+
+       ret = abx500_set_register_interruptible(chip->dev, AB8500_MISC,
+                       reg, (u8)lower_val);
+       if (ret < 0)
+               return ret;
+       ret = abx500_set_register_interruptible(chip->dev, AB8500_MISC,
+                       (reg + 1), (u8)higher_val);
+
+       return ret;
+}
+
+static int ab8500_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+       int ret;
+
+       ret = abx500_mask_and_set_register_interruptible(chip->dev,
+                               AB8500_MISC, AB8500_PWM_OUT_CTRL7_REG,
+                               1 << (chip->base - 1), 1 << (chip->base - 1));
+       if (ret < 0)
+               dev_err(chip->dev, "%s: Failed to enable PWM, Error %d\n",
+                                                       pwm->label, ret);
+       return ret;
+}
+
+static void ab8500_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+       int ret;
+
+       ret = abx500_mask_and_set_register_interruptible(chip->dev,
+                               AB8500_MISC, AB8500_PWM_OUT_CTRL7_REG,
+                               1 << (chip->base - 1), 0);
+       if (ret < 0)
+               dev_err(chip->dev, "%s: Failed to disable PWM, Error %d\n",
+                                                       pwm->label, ret);
+}
+
+static const struct pwm_ops ab8500_pwm_ops = {
+       .config = ab8500_pwm_config,
+       .enable = ab8500_pwm_enable,
+       .disable = ab8500_pwm_disable,
+       .owner = THIS_MODULE,
+};
+
+static int ab8500_pwm_probe(struct platform_device *pdev)
+{
+       struct ab8500_pwm_chip *ab8500;
+       int err;
+
+       /*
+        * Nothing to be done in probe, this is required to get the
+        * device which is required for ab8500 read and write
+        */
+       ab8500 = devm_kzalloc(&pdev->dev, sizeof(*ab8500), GFP_KERNEL);
+       if (ab8500 == NULL)
+               return -ENOMEM;
+
+       ab8500->chip.dev = &pdev->dev;
+       ab8500->chip.ops = &ab8500_pwm_ops;
+       ab8500->chip.base = pdev->id;
+       ab8500->chip.npwm = 1;
+
+       err = pwmchip_add(&ab8500->chip);
+       if (err < 0)
+               return err;
+
+       dev_dbg(&pdev->dev, "pwm probe successful\n");
+       platform_set_drvdata(pdev, ab8500);
+
+       return 0;
+}
+
+static int ab8500_pwm_remove(struct platform_device *pdev)
+{
+       struct ab8500_pwm_chip *ab8500 = platform_get_drvdata(pdev);
+       int err;
+
+       err = pwmchip_remove(&ab8500->chip);
+       if (err < 0)
+               return err;
+
+       dev_dbg(&pdev->dev, "pwm driver removed\n");
+
+       return 0;
+}
+
+static struct platform_driver ab8500_pwm_driver = {
+       .driver = {
+               .name = "ab8500-pwm",
+       },
+       .probe = ab8500_pwm_probe,
+       .remove = ab8500_pwm_remove,
+};
+module_platform_driver(ab8500_pwm_driver);
+
+MODULE_AUTHOR("Arun MURTHY <arun.murthy@stericsson.com>");
+MODULE_DESCRIPTION("AB8500 Pulse Width Modulation Driver");
+MODULE_ALIAS("platform:ab8500-pwm");
+MODULE_LICENSE("GPL v2");