diff options
author | H Hartley Sweeten <hartleys@visionengravers.com> | 2013-10-15 18:40:03 -0700 |
---|---|---|
committer | Thierry Reding <thierry.reding@gmail.com> | 2013-10-17 16:07:19 +0200 |
commit | a23086981723570c8952520d9ffaf6995d45f63e (patch) | |
tree | 954638f3a758cea41ea59affcdf213fa83c61af0 | |
parent | 8f43e18e2769b3b28383903d501b4da29e388aad (diff) | |
download | linux-a23086981723570c8952520d9ffaf6995d45f63e.tar.bz2 |
pwm: add ep93xx PWM support
Remove the non-standard EP93xx PWM driver in drivers/misc and add
a new driver for the PWM controllers on the EP93xx platform based
on the PWM framework.
These PWM controllers each support 1 PWM channel with programmable
duty cycle, frequency, and polarity inversion.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Ryan Mallon <rmallon@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
-rw-r--r-- | drivers/misc/Kconfig | 13 | ||||
-rw-r--r-- | drivers/misc/Makefile | 1 | ||||
-rw-r--r-- | drivers/misc/ep93xx_pwm.c | 286 | ||||
-rw-r--r-- | drivers/pwm/Kconfig | 9 | ||||
-rw-r--r-- | drivers/pwm/Makefile | 1 | ||||
-rw-r--r-- | drivers/pwm/pwm-ep93xx.c | 230 |
6 files changed, 240 insertions, 300 deletions
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig index 8dacd4c9ee87..c43c66ad5721 100644 --- a/drivers/misc/Kconfig +++ b/drivers/misc/Kconfig @@ -381,19 +381,6 @@ config HMC6352 This driver provides support for the Honeywell HMC6352 compass, providing configuration and heading data via sysfs. -config EP93XX_PWM - tristate "EP93xx PWM support" - depends on ARCH_EP93XX - help - This option enables device driver support for the PWM channels - on the Cirrus EP93xx processors. The EP9307 chip only has one - PWM channel all the others have two, the second channel is an - alternate function of the EGPIO14 pin. A sysfs interface is - provided to control the PWM channels. - - To compile this driver as a module, choose M here: the module will - be called ep93xx_pwm. - config DS1682 tristate "Dallas DS1682 Total Elapsed Time Recorder with Alarm" depends on I2C diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile index c235d5b68311..ecccd0039353 100644 --- a/drivers/misc/Makefile +++ b/drivers/misc/Makefile @@ -33,7 +33,6 @@ obj-$(CONFIG_APDS9802ALS) += apds9802als.o obj-$(CONFIG_ISL29003) += isl29003.o obj-$(CONFIG_ISL29020) += isl29020.o obj-$(CONFIG_SENSORS_TSL2550) += tsl2550.o -obj-$(CONFIG_EP93XX_PWM) += ep93xx_pwm.o obj-$(CONFIG_DS1682) += ds1682.o obj-$(CONFIG_TI_DAC7512) += ti_dac7512.o obj-$(CONFIG_C2PORT) += c2port/ diff --git a/drivers/misc/ep93xx_pwm.c b/drivers/misc/ep93xx_pwm.c deleted file mode 100644 index cdb67a9c1959..000000000000 --- a/drivers/misc/ep93xx_pwm.c +++ /dev/null @@ -1,286 +0,0 @@ -/* - * Simple PWM driver for EP93XX - * - * (c) Copyright 2009 Matthieu Crapet <mcrapet@gmail.com> - * (c) Copyright 2009 H Hartley Sweeten <hsweeten@visionengravers.com> - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version - * 2 of the License, or (at your option) any later version. - * - * EP9307 has only one channel: - * - PWMOUT - * - * EP9301/02/12/15 have two channels: - * - PWMOUT - * - PWMOUT1 (alternate function for EGPIO14) - */ - -#include <linux/module.h> -#include <linux/platform_device.h> -#include <linux/slab.h> -#include <linux/clk.h> -#include <linux/err.h> -#include <linux/io.h> - -#include <mach/platform.h> - -#define EP93XX_PWMx_TERM_COUNT 0x00 -#define EP93XX_PWMx_DUTY_CYCLE 0x04 -#define EP93XX_PWMx_ENABLE 0x08 -#define EP93XX_PWMx_INVERT 0x0C - -#define EP93XX_PWM_MAX_COUNT 0xFFFF - -struct ep93xx_pwm { - void __iomem *mmio_base; - struct clk *clk; - u32 duty_percent; -}; - -/* - * /sys/devices/platform/ep93xx-pwm.N - * /min_freq read-only minimum pwm output frequency - * /max_req read-only maximum pwm output frequency - * /freq read-write pwm output frequency (0 = disable output) - * /duty_percent read-write pwm duty cycle percent (1..99) - * /invert read-write invert pwm output - */ - -static ssize_t ep93xx_pwm_get_min_freq(struct device *dev, - struct device_attribute *attr, char *buf) -{ - struct platform_device *pdev = to_platform_device(dev); - struct ep93xx_pwm *pwm = platform_get_drvdata(pdev); - unsigned long rate = clk_get_rate(pwm->clk); - - return sprintf(buf, "%ld\n", rate / (EP93XX_PWM_MAX_COUNT + 1)); -} - -static ssize_t ep93xx_pwm_get_max_freq(struct device *dev, - struct device_attribute *attr, char *buf) -{ - struct platform_device *pdev = to_platform_device(dev); - struct ep93xx_pwm *pwm = platform_get_drvdata(pdev); - unsigned long rate = clk_get_rate(pwm->clk); - - return sprintf(buf, "%ld\n", rate / 2); -} - -static ssize_t ep93xx_pwm_get_freq(struct device *dev, - struct device_attribute *attr, char *buf) -{ - struct platform_device *pdev = to_platform_device(dev); - struct ep93xx_pwm *pwm = platform_get_drvdata(pdev); - - if (readl(pwm->mmio_base + EP93XX_PWMx_ENABLE) & 0x1) { - unsigned long rate = clk_get_rate(pwm->clk); - u16 term = readl(pwm->mmio_base + EP93XX_PWMx_TERM_COUNT); - - return sprintf(buf, "%ld\n", rate / (term + 1)); - } else { - return sprintf(buf, "disabled\n"); - } -} - -static ssize_t ep93xx_pwm_set_freq(struct device *dev, - struct device_attribute *attr, const char *buf, size_t count) -{ - struct platform_device *pdev = to_platform_device(dev); - struct ep93xx_pwm *pwm = platform_get_drvdata(pdev); - long val; - int err; - - err = kstrtol(buf, 10, &val); - if (err) - return -EINVAL; - - if (val == 0) { - writel(0x0, pwm->mmio_base + EP93XX_PWMx_ENABLE); - } else if (val <= (clk_get_rate(pwm->clk) / 2)) { - u32 term, duty; - - val = (clk_get_rate(pwm->clk) / val) - 1; - if (val > EP93XX_PWM_MAX_COUNT) - val = EP93XX_PWM_MAX_COUNT; - if (val < 1) - val = 1; - - term = readl(pwm->mmio_base + EP93XX_PWMx_TERM_COUNT); - duty = ((val + 1) * pwm->duty_percent / 100) - 1; - - /* If pwm is running, order is important */ - if (val > term) { - writel(val, pwm->mmio_base + EP93XX_PWMx_TERM_COUNT); - writel(duty, pwm->mmio_base + EP93XX_PWMx_DUTY_CYCLE); - } else { - writel(duty, pwm->mmio_base + EP93XX_PWMx_DUTY_CYCLE); - writel(val, pwm->mmio_base + EP93XX_PWMx_TERM_COUNT); - } - - if (!readl(pwm->mmio_base + EP93XX_PWMx_ENABLE) & 0x1) - writel(0x1, pwm->mmio_base + EP93XX_PWMx_ENABLE); - } else { - return -EINVAL; - } - - return count; -} - -static ssize_t ep93xx_pwm_get_duty_percent(struct device *dev, - struct device_attribute *attr, char *buf) -{ - struct platform_device *pdev = to_platform_device(dev); - struct ep93xx_pwm *pwm = platform_get_drvdata(pdev); - - return sprintf(buf, "%d\n", pwm->duty_percent); -} - -static ssize_t ep93xx_pwm_set_duty_percent(struct device *dev, - struct device_attribute *attr, const char *buf, size_t count) -{ - struct platform_device *pdev = to_platform_device(dev); - struct ep93xx_pwm *pwm = platform_get_drvdata(pdev); - long val; - int err; - - err = kstrtol(buf, 10, &val); - if (err) - return -EINVAL; - - if (val > 0 && val < 100) { - u32 term = readl(pwm->mmio_base + EP93XX_PWMx_TERM_COUNT); - u32 duty = ((term + 1) * val / 100) - 1; - - writel(duty, pwm->mmio_base + EP93XX_PWMx_DUTY_CYCLE); - pwm->duty_percent = val; - return count; - } - - return -EINVAL; -} - -static ssize_t ep93xx_pwm_get_invert(struct device *dev, - struct device_attribute *attr, char *buf) -{ - struct platform_device *pdev = to_platform_device(dev); - struct ep93xx_pwm *pwm = platform_get_drvdata(pdev); - int inverted = readl(pwm->mmio_base + EP93XX_PWMx_INVERT) & 0x1; - - return sprintf(buf, "%d\n", inverted); -} - -static ssize_t ep93xx_pwm_set_invert(struct device *dev, - struct device_attribute *attr, const char *buf, size_t count) -{ - struct platform_device *pdev = to_platform_device(dev); - struct ep93xx_pwm *pwm = platform_get_drvdata(pdev); - long val; - int err; - - err = kstrtol(buf, 10, &val); - if (err) - return -EINVAL; - - if (val == 0) - writel(0x0, pwm->mmio_base + EP93XX_PWMx_INVERT); - else if (val == 1) - writel(0x1, pwm->mmio_base + EP93XX_PWMx_INVERT); - else - return -EINVAL; - - return count; -} - -static DEVICE_ATTR(min_freq, S_IRUGO, ep93xx_pwm_get_min_freq, NULL); -static DEVICE_ATTR(max_freq, S_IRUGO, ep93xx_pwm_get_max_freq, NULL); -static DEVICE_ATTR(freq, S_IWUSR | S_IRUGO, - ep93xx_pwm_get_freq, ep93xx_pwm_set_freq); -static DEVICE_ATTR(duty_percent, S_IWUSR | S_IRUGO, - ep93xx_pwm_get_duty_percent, ep93xx_pwm_set_duty_percent); -static DEVICE_ATTR(invert, S_IWUSR | S_IRUGO, - ep93xx_pwm_get_invert, ep93xx_pwm_set_invert); - -static struct attribute *ep93xx_pwm_attrs[] = { - &dev_attr_min_freq.attr, - &dev_attr_max_freq.attr, - &dev_attr_freq.attr, - &dev_attr_duty_percent.attr, - &dev_attr_invert.attr, - NULL -}; - -static const struct attribute_group ep93xx_pwm_sysfs_files = { - .attrs = ep93xx_pwm_attrs, -}; - -static int ep93xx_pwm_probe(struct platform_device *pdev) -{ - struct ep93xx_pwm *pwm; - struct resource *res; - int ret; - - pwm = devm_kzalloc(&pdev->dev, sizeof(*pwm), GFP_KERNEL); - if (!pwm) - return -ENOMEM; - - pwm->clk = devm_clk_get(&pdev->dev, "pwm_clk"); - if (IS_ERR(pwm->clk)) - return PTR_ERR(pwm->clk); - - res = platform_get_resource(pdev, IORESOURCE_MEM, 0); - pwm->mmio_base = devm_ioremap_resource(&pdev->dev, res); - if (IS_ERR(pwm->mmio_base)) - return PTR_ERR(pwm->mmio_base); - - ret = ep93xx_pwm_acquire_gpio(pdev); - if (ret) - return ret; - - ret = sysfs_create_group(&pdev->dev.kobj, &ep93xx_pwm_sysfs_files); - if (ret) { - ep93xx_pwm_release_gpio(pdev); - return ret; - } - - pwm->duty_percent = 50; - - /* disable pwm at startup. Avoids zero value. */ - writel(0x0, pwm->mmio_base + EP93XX_PWMx_ENABLE); - writel(EP93XX_PWM_MAX_COUNT, pwm->mmio_base + EP93XX_PWMx_TERM_COUNT); - writel(EP93XX_PWM_MAX_COUNT/2, pwm->mmio_base + EP93XX_PWMx_DUTY_CYCLE); - - clk_enable(pwm->clk); - - platform_set_drvdata(pdev, pwm); - return 0; -} - -static int ep93xx_pwm_remove(struct platform_device *pdev) -{ - struct ep93xx_pwm *pwm = platform_get_drvdata(pdev); - - writel(0x0, pwm->mmio_base + EP93XX_PWMx_ENABLE); - clk_disable(pwm->clk); - sysfs_remove_group(&pdev->dev.kobj, &ep93xx_pwm_sysfs_files); - ep93xx_pwm_release_gpio(pdev); - - return 0; -} - -static struct platform_driver ep93xx_pwm_driver = { - .driver = { - .name = "ep93xx-pwm", - .owner = THIS_MODULE, - }, - .probe = ep93xx_pwm_probe, - .remove = ep93xx_pwm_remove, -}; -module_platform_driver(ep93xx_pwm_driver); - -MODULE_AUTHOR("Matthieu Crapet <mcrapet@gmail.com>, " - "H Hartley Sweeten <hsweeten@visionengravers.com>"); -MODULE_DESCRIPTION("EP93xx PWM driver"); -MODULE_LICENSE("GPL"); -MODULE_ALIAS("platform:ep93xx-pwm"); diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig index 75840b5cea6d..eece329d7872 100644 --- a/drivers/pwm/Kconfig +++ b/drivers/pwm/Kconfig @@ -62,6 +62,15 @@ config PWM_BFIN To compile this driver as a module, choose M here: the module will be called pwm-bfin. +config PWM_EP93XX + tristate "Cirrus Logic EP93xx PWM support" + depends on ARCH_EP93XX + help + Generic PWM framework driver for Cirrus Logic EP93xx. + + To compile this driver as a module, choose M here: the module + will be called pwm-ep93xx. + config PWM_IMX tristate "i.MX PWM support" depends on ARCH_MXC diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile index 77a8c185c5b2..8b754e4dba4a 100644 --- a/drivers/pwm/Makefile +++ b/drivers/pwm/Makefile @@ -3,6 +3,7 @@ obj-$(CONFIG_PWM_SYSFS) += sysfs.o obj-$(CONFIG_PWM_AB8500) += pwm-ab8500.o obj-$(CONFIG_PWM_ATMEL_TCB) += pwm-atmel-tcb.o obj-$(CONFIG_PWM_BFIN) += pwm-bfin.o +obj-$(CONFIG_PWM_EP93XX) += pwm-ep93xx.o obj-$(CONFIG_PWM_IMX) += pwm-imx.o obj-$(CONFIG_PWM_JZ4740) += pwm-jz4740.o obj-$(CONFIG_PWM_LPC32XX) += pwm-lpc32xx.o diff --git a/drivers/pwm/pwm-ep93xx.c b/drivers/pwm/pwm-ep93xx.c new file mode 100644 index 000000000000..33aa4461e1ce --- /dev/null +++ b/drivers/pwm/pwm-ep93xx.c @@ -0,0 +1,230 @@ +/* + * PWM framework driver for Cirrus Logic EP93xx + * + * Copyright (c) 2009 Matthieu Crapet <mcrapet@gmail.com> + * Copyright (c) 2009, 2013 H Hartley Sweeten <hsweeten@visionengravers.com> + * + * EP9301/02 have only one channel: + * platform device ep93xx-pwm.1 - PWMOUT1 (EGPIO14) + * + * EP9307 has only one channel: + * platform device ep93xx-pwm.0 - PWMOUT + * + * EP9312/15 have two channels: + * platform device ep93xx-pwm.0 - PWMOUT + * platform device ep93xx-pwm.1 - PWMOUT1 (EGPIO14) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + * + * 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. + */ + +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/clk.h> +#include <linux/err.h> +#include <linux/io.h> +#include <linux/pwm.h> + +#include <asm/div64.h> + +#include <mach/platform.h> /* for ep93xx_pwm_{acquire,release}_gpio() */ + +#define EP93XX_PWMx_TERM_COUNT 0x00 +#define EP93XX_PWMx_DUTY_CYCLE 0x04 +#define EP93XX_PWMx_ENABLE 0x08 +#define EP93XX_PWMx_INVERT 0x0c + +struct ep93xx_pwm { + void __iomem *base; + struct clk *clk; + struct pwm_chip chip; +}; + +static inline struct ep93xx_pwm *to_ep93xx_pwm(struct pwm_chip *chip) +{ + return container_of(chip, struct ep93xx_pwm, chip); +} + +static int ep93xx_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm) +{ + struct platform_device *pdev = to_platform_device(chip->dev); + + return ep93xx_pwm_acquire_gpio(pdev); +} + +static void ep93xx_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm) +{ + struct platform_device *pdev = to_platform_device(chip->dev); + + ep93xx_pwm_release_gpio(pdev); +} + +static int ep93xx_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, + int duty_ns, int period_ns) +{ + struct ep93xx_pwm *ep93xx_pwm = to_ep93xx_pwm(chip); + void __iomem *base = ep93xx_pwm->base; + unsigned long long c; + unsigned long period_cycles; + unsigned long duty_cycles; + unsigned long term; + int ret = 0; + + /* + * The clock needs to be enabled to access the PWM registers. + * Configuration can be changed at any time. + */ + if (!test_bit(PWMF_ENABLED, &pwm->flags)) { + ret = clk_enable(ep93xx_pwm->clk); + if (ret) + return ret; + } + + c = clk_get_rate(ep93xx_pwm->clk); + c *= period_ns; + do_div(c, 1000000000); + period_cycles = c; + + c = period_cycles; + c *= duty_ns; + do_div(c, period_ns); + duty_cycles = c; + + if (period_cycles < 0x10000 && duty_cycles < 0x10000) { + term = readw(base + EP93XX_PWMx_TERM_COUNT); + + /* Order is important if PWM is running */ + if (period_cycles > term) { + writew(period_cycles, base + EP93XX_PWMx_TERM_COUNT); + writew(duty_cycles, base + EP93XX_PWMx_DUTY_CYCLE); + } else { + writew(duty_cycles, base + EP93XX_PWMx_DUTY_CYCLE); + writew(period_cycles, base + EP93XX_PWMx_TERM_COUNT); + } + } else { + ret = -EINVAL; + } + + if (!test_bit(PWMF_ENABLED, &pwm->flags)) + clk_disable(ep93xx_pwm->clk); + + return ret; +} + +static int ep93xx_pwm_polarity(struct pwm_chip *chip, struct pwm_device *pwm, + enum pwm_polarity polarity) +{ + struct ep93xx_pwm *ep93xx_pwm = to_ep93xx_pwm(chip); + int ret; + + /* + * The clock needs to be enabled to access the PWM registers. + * Polarity can only be changed when the PWM is disabled. + */ + ret = clk_enable(ep93xx_pwm->clk); + if (ret) + return ret; + + if (polarity == PWM_POLARITY_INVERSED) + writew(0x1, ep93xx_pwm->base + EP93XX_PWMx_INVERT); + else + writew(0x0, ep93xx_pwm->base + EP93XX_PWMx_INVERT); + + clk_disable(ep93xx_pwm->clk); + + return 0; +} + +static int ep93xx_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) +{ + struct ep93xx_pwm *ep93xx_pwm = to_ep93xx_pwm(chip); + int ret; + + ret = clk_enable(ep93xx_pwm->clk); + if (ret) + return ret; + + writew(0x1, ep93xx_pwm->base + EP93XX_PWMx_ENABLE); + + return 0; +} + +static void ep93xx_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) +{ + struct ep93xx_pwm *ep93xx_pwm = to_ep93xx_pwm(chip); + + writew(0x0, ep93xx_pwm->base + EP93XX_PWMx_ENABLE); + clk_disable(ep93xx_pwm->clk); +} + +static const struct pwm_ops ep93xx_pwm_ops = { + .request = ep93xx_pwm_request, + .free = ep93xx_pwm_free, + .config = ep93xx_pwm_config, + .set_polarity = ep93xx_pwm_polarity, + .enable = ep93xx_pwm_enable, + .disable = ep93xx_pwm_disable, + .owner = THIS_MODULE, +}; + +static int ep93xx_pwm_probe(struct platform_device *pdev) +{ + struct ep93xx_pwm *ep93xx_pwm; + struct resource *res; + int ret; + + ep93xx_pwm = devm_kzalloc(&pdev->dev, sizeof(*ep93xx_pwm), GFP_KERNEL); + if (!ep93xx_pwm) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + ep93xx_pwm->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(ep93xx_pwm->base)) + return PTR_ERR(ep93xx_pwm->base); + + ep93xx_pwm->clk = devm_clk_get(&pdev->dev, "pwm_clk"); + if (IS_ERR(ep93xx_pwm->clk)) + return PTR_ERR(ep93xx_pwm->clk); + + ep93xx_pwm->chip.dev = &pdev->dev; + ep93xx_pwm->chip.ops = &ep93xx_pwm_ops; + ep93xx_pwm->chip.base = -1; + ep93xx_pwm->chip.npwm = 1; + + ret = pwmchip_add(&ep93xx_pwm->chip); + if (ret < 0) + return ret; + + platform_set_drvdata(pdev, ep93xx_pwm); + return 0; +} + +static int ep93xx_pwm_remove(struct platform_device *pdev) +{ + struct ep93xx_pwm *ep93xx_pwm = platform_get_drvdata(pdev); + + return pwmchip_remove(&ep93xx_pwm->chip); +} + +static struct platform_driver ep93xx_pwm_driver = { + .driver = { + .name = "ep93xx-pwm", + }, + .probe = ep93xx_pwm_probe, + .remove = ep93xx_pwm_remove, +}; +module_platform_driver(ep93xx_pwm_driver); + +MODULE_DESCRIPTION("Cirrus Logic EP93xx PWM driver"); +MODULE_AUTHOR("Matthieu Crapet <mcrapet@gmail.com>, " + "H Hartley Sweeten <hsweeten@visionengravers.com>"); +MODULE_ALIAS("platform:ep93xx-pwm"); +MODULE_LICENSE("GPL"); |