diff options
Diffstat (limited to 'drivers/pwm')
| -rw-r--r-- | drivers/pwm/Kconfig | 40 | ||||
| -rw-r--r-- | drivers/pwm/Makefile | 1 | ||||
| -rw-r--r-- | drivers/pwm/core.c | 12 | ||||
| -rw-r--r-- | drivers/pwm/pwm-samsung.c | 1 | ||||
| -rw-r--r-- | drivers/pwm/pwm-tegra.c | 4 | ||||
| -rw-r--r-- | drivers/pwm/pwm-tiecap.c | 11 | ||||
| -rw-r--r-- | drivers/pwm/pwm-tiehrpwm.c | 33 | ||||
| -rw-r--r-- | drivers/pwm/pwm-twl6030.c | 184 | ||||
| -rw-r--r-- | drivers/pwm/pwm-vt8500.c | 2 |
9 files changed, 266 insertions, 22 deletions
diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig index 8fc3808d7a3e..d7c6b83097c1 100644 --- a/drivers/pwm/Kconfig +++ b/drivers/pwm/Kconfig @@ -1,12 +1,31 @@ menuconfig PWM - bool "PWM Support" + bool "Pulse-Width Modulation (PWM) Support" depends on !MACH_JZ4740 && !PUV3_PWM help - This enables PWM support through the generic PWM framework. - You only need to enable this, if you also want to enable - one or more of the PWM drivers below. - - If unsure, say N. + Generic Pulse-Width Modulation (PWM) support. + + In Pulse-Width Modulation, a variation of the width of pulses + in a rectangular pulse signal is used as a means to alter the + average power of the signal. Applications include efficient + power delivery and voltage regulation. In computer systems, + PWMs are commonly used to control fans or the brightness of + display backlights. + + This framework provides a generic interface to PWM devices + within the Linux kernel. On the driver side it provides an API + to register and unregister a PWM chip, an abstraction of a PWM + controller, that supports one or more PWM devices. Client + drivers can request PWM devices and use the generic framework + to configure as well as enable and disable them. + + This generic framework replaces the legacy PWM framework which + allows only a single driver implementing the required API. Not + all legacy implementations have been ported to the framework + yet. The framework provides an API that is backward compatible + with the legacy framework so that existing client drivers + continue to work as expected. + + If unsure, say no. if PWM @@ -96,6 +115,15 @@ 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/pwm/core.c b/drivers/pwm/core.c index ecb76909e946..c6e05078d3ad 100644 --- a/drivers/pwm/core.c +++ b/drivers/pwm/core.c @@ -129,8 +129,8 @@ static int pwm_device_request(struct pwm_device *pwm, const char *label) return 0; } -static struct pwm_device *of_pwm_simple_xlate(struct pwm_chip *pc, - const struct of_phandle_args *args) +static struct pwm_device * +of_pwm_simple_xlate(struct pwm_chip *pc, const struct of_phandle_args *args) { struct pwm_device *pwm; @@ -149,7 +149,7 @@ static struct pwm_device *of_pwm_simple_xlate(struct pwm_chip *pc, return pwm; } -void of_pwmchip_add(struct pwm_chip *chip) +static void of_pwmchip_add(struct pwm_chip *chip) { if (!chip->dev || !chip->dev->of_node) return; @@ -162,7 +162,7 @@ void of_pwmchip_add(struct pwm_chip *chip) of_node_get(chip->dev->of_node); } -void of_pwmchip_remove(struct pwm_chip *chip) +static void of_pwmchip_remove(struct pwm_chip *chip) { if (chip->dev && chip->dev->of_node) of_node_put(chip->dev->of_node); @@ -527,7 +527,7 @@ void __init pwm_add_table(struct pwm_lookup *table, size_t num) struct pwm_device *pwm_get(struct device *dev, const char *con_id) { struct pwm_device *pwm = ERR_PTR(-EPROBE_DEFER); - const char *dev_id = dev ? dev_name(dev): NULL; + const char *dev_id = dev ? dev_name(dev) : NULL; struct pwm_chip *chip = NULL; unsigned int index = 0; unsigned int best = 0; @@ -609,7 +609,7 @@ void pwm_put(struct pwm_device *pwm) mutex_lock(&pwm_lock); if (!test_and_clear_bit(PWMF_REQUESTED, &pwm->flags)) { - pr_warning("PWM device already freed\n"); + pr_warn("PWM device already freed\n"); goto out; } diff --git a/drivers/pwm/pwm-samsung.c b/drivers/pwm/pwm-samsung.c index d10386528c9c..e5187c0ade9f 100644 --- a/drivers/pwm/pwm-samsung.c +++ b/drivers/pwm/pwm-samsung.c @@ -225,6 +225,7 @@ static int s3c_pwm_probe(struct platform_device *pdev) /* calculate base of control bits in TCON */ s3c->tcon_base = id == 0 ? 0 : (id * 4) + 4; + s3c->chip.dev = &pdev->dev; s3c->chip.ops = &s3c_pwm_ops; s3c->chip.base = -1; s3c->chip.npwm = 1; diff --git a/drivers/pwm/pwm-tegra.c b/drivers/pwm/pwm-tegra.c index 02ce18d5e49a..057465e0553c 100644 --- a/drivers/pwm/pwm-tegra.c +++ b/drivers/pwm/pwm-tegra.c @@ -187,10 +187,8 @@ static int tegra_pwm_probe(struct platform_device *pdev) } pwm->mmio_base = devm_request_and_ioremap(&pdev->dev, r); - if (!pwm->mmio_base) { - dev_err(&pdev->dev, "failed to ioremap() region\n"); + if (!pwm->mmio_base) return -EADDRNOTAVAIL; - } platform_set_drvdata(pdev, pwm); diff --git a/drivers/pwm/pwm-tiecap.c b/drivers/pwm/pwm-tiecap.c index 3c2ad284ee3e..4b6688909fee 100644 --- a/drivers/pwm/pwm-tiecap.c +++ b/drivers/pwm/pwm-tiecap.c @@ -100,6 +100,13 @@ static int ecap_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, writel(period_cycles, pc->mmio_base + CAP3); } + if (!test_bit(PWMF_ENABLED, &pwm->flags)) { + reg_val = readw(pc->mmio_base + ECCTL2); + /* Disable APWM mode to put APWM output Low */ + reg_val &= ~ECCTL2_APWM_MODE; + writew(reg_val, pc->mmio_base + ECCTL2); + } + pm_runtime_put_sync(pc->chip.dev); return 0; } @@ -192,10 +199,8 @@ static int __devinit ecap_pwm_probe(struct platform_device *pdev) } pc->mmio_base = devm_request_and_ioremap(&pdev->dev, r); - if (!pc->mmio_base) { - dev_err(&pdev->dev, "failed to ioremap() registers\n"); + if (!pc->mmio_base) return -EADDRNOTAVAIL; - } ret = pwmchip_add(&pc->chip); if (ret < 0) { diff --git a/drivers/pwm/pwm-tiehrpwm.c b/drivers/pwm/pwm-tiehrpwm.c index 010d232cb0c8..b1996bcd5b78 100644 --- a/drivers/pwm/pwm-tiehrpwm.c +++ b/drivers/pwm/pwm-tiehrpwm.c @@ -104,6 +104,7 @@ struct ehrpwm_pwm_chip { struct pwm_chip chip; unsigned int clk_rate; void __iomem *mmio_base; + unsigned long period_cycles[NUM_PWM_CHANNEL]; }; static inline struct ehrpwm_pwm_chip *to_ehrpwm_pwm_chip(struct pwm_chip *chip) @@ -210,6 +211,7 @@ static int ehrpwm_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, unsigned long long c; unsigned long period_cycles, duty_cycles; unsigned short ps_divval, tb_divval; + int i; if (period_ns < 0 || duty_ns < 0 || period_ns > NSEC_PER_SEC) return -ERANGE; @@ -229,6 +231,28 @@ static int ehrpwm_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, duty_cycles = (unsigned long)c; } + /* + * Period values should be same for multiple PWM channels as IP uses + * same period register for multiple channels. + */ + for (i = 0; i < NUM_PWM_CHANNEL; i++) { + if (pc->period_cycles[i] && + (pc->period_cycles[i] != period_cycles)) { + /* + * Allow channel to reconfigure period if no other + * channels being configured. + */ + if (i == pwm->hwpwm) + continue; + + dev_err(chip->dev, "Period value conflicts with channel %d\n", + i); + return -EINVAL; + } + } + + pc->period_cycles[pwm->hwpwm] = period_cycles; + /* Configure clock prescaler to support Low frequency PWM wave */ if (set_prescale_div(period_cycles/PERIOD_MAX, &ps_divval, &tb_divval)) { @@ -320,10 +344,15 @@ static void ehrpwm_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) static void ehrpwm_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm) { + struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip); + if (test_bit(PWMF_ENABLED, &pwm->flags)) { dev_warn(chip->dev, "Removing PWM device without disabling\n"); pm_runtime_put_sync(chip->dev); } + + /* set period value to zero on free */ + pc->period_cycles[pwm->hwpwm] = 0; } static const struct pwm_ops ehrpwm_pwm_ops = { @@ -371,10 +400,8 @@ static int __devinit ehrpwm_pwm_probe(struct platform_device *pdev) } pc->mmio_base = devm_request_and_ioremap(&pdev->dev, r); - if (!pc->mmio_base) { - dev_err(&pdev->dev, "failed to ioremap() registers\n"); + if (!pc->mmio_base) return -EADDRNOTAVAIL; - } ret = pwmchip_add(&pc->chip); if (ret < 0) { 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"); diff --git a/drivers/pwm/pwm-vt8500.c b/drivers/pwm/pwm-vt8500.c index 548021439f0c..ad14389b7144 100644 --- a/drivers/pwm/pwm-vt8500.c +++ b/drivers/pwm/pwm-vt8500.c @@ -41,7 +41,7 @@ static inline void pwm_busy_wait(void __iomem *reg, u8 bitmask) cpu_relax(); if (unlikely(!loops)) - pr_warning("Waiting for status bits 0x%x to clear timed out\n", + pr_warn("Waiting for status bits 0x%x to clear timed out\n", bitmask); } |