/* * Copyright (C) ST-Ericsson SA 2010 * * Author: Arun R Murthy * License terms: GNU General Public License (GPL) version 2 */ #include #include #include #include #include #include #include #include #include /* * 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 num_pwm; 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; } EXPORT_SYMBOL(pwm_config_blink); 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; } EXPORT_SYMBOL(pwm_blink_ctrl); 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 ssize_t store_blink_status(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct pwm_device *pwm; unsigned long val; if (strict_strtoul(buf, 0, &val)) return -EINVAL; list_for_each_entry(pwm, &pwm_list, node) { if (pwm->pwm_id == val) break; else { /* check if PWM ID is valid*/ if (val > pwm->num_pwm) { dev_err(pwm->dev, "Invalid PWM ID\n"); return -EINVAL; } } } if ((!is_ab8505(pwm->parent)) || (!pwm->blink_en)) { dev_err(pwm->dev, "setting blinking for this " "device not supported\n"); return -EINVAL; } /*Disable blink functionlity */ pwm_blink_ctrl(pwm, 0); return count; } static DEVICE_ATTR(disable_blink, S_IWUGO, NULL, store_blink_status); static struct attribute *pwmled_attributes[] = { &dev_attr_disable_blink.attr, NULL }; static const struct attribute_group pwmled_attr_group = { .attrs = pwmled_attributes, }; 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; struct pwm_device *pwm; int ret = 0 , i; /* get pwmled specific platform data */ if (!plat->pwmled) { dev_err(&pdev->dev, "no pwm platform data supplied\n"); return -EINVAL; } pdata = plat->pwmled; /* * 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; pwm[i].num_pwm = pdata->num_pwm; list_add_tail(&pwm[i].node, &pwm_list); } for (i = 0; i < pdata->num_pwm; i++) { /*Implement sysfs only if blink is enabled*/ if ((is_ab8505(pwm[i].parent)) && (pwm[i].blink_en)) { /* sysfs implementation to disable the blink */ ret = sysfs_create_group(&pdev->dev.kobj, &pwmled_attr_group); if (ret) { dev_err(&pdev->dev, "failed to create" " sysfs entries\n"); goto fail; } break; } } 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 err_clk; } platform_set_drvdata(pdev, pwm); pwm->clk_enabled = false; dev_dbg(pwm->dev, "pwm probe successful\n"); return ret; err_clk: for (i = 0; i < pdata->num_pwm; i++) { if ((is_ab8505(pwm[i].parent)) && (pwm[i].blink_en)) { sysfs_remove_group(&pdev->dev.kobj, &pwmled_attr_group); break; } } 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); int i; for (i = 0; i < pwm->num_pwm; i++) { if ((is_ab8505(pwm[i].parent)) && (pwm[i].blink_en)) { sysfs_remove_group(&pdev->dev.kobj, &pwmled_attr_group); break; } } 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 "); MODULE_DESCRIPTION("AB8500 Pulse Width Modulation Driver"); MODULE_ALIAS("platform:ab8500-pwm"); MODULE_LICENSE("GPL v2");