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Diffstat (limited to 'target/linux/xburst/patches-2.6.35/011-pwm.patch')
-rw-r--r--target/linux/xburst/patches-2.6.35/011-pwm.patch197
1 files changed, 197 insertions, 0 deletions
diff --git a/target/linux/xburst/patches-2.6.35/011-pwm.patch b/target/linux/xburst/patches-2.6.35/011-pwm.patch
new file mode 100644
index 0000000000..3c8336baae
--- /dev/null
+++ b/target/linux/xburst/patches-2.6.35/011-pwm.patch
@@ -0,0 +1,197 @@
+From 5cd5a44b94b451ecaf593bb49919cfbb51ccb622 Mon Sep 17 00:00:00 2001
+From: Lars-Peter Clausen <lars@metafoo.de>
+Date: Sat, 17 Jul 2010 11:12:20 +0000
+Subject: [PATCH] MIPS: JZ4740: Add PWM support
+
+Add support for the PWM part of the timer unit on a JZ4740 SoC.
+
+Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
+Cc: linux-mips@linux-mips.org
+Cc: linux-kernel@vger.kernel.org
+Patchwork: https://patchwork.linux-mips.org/patch/1468/
+Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
+---
+ arch/mips/jz4740/pwm.c | 177 ++++++++++++++++++++++++++++++++++++++++++++++++
+ 1 files changed, 177 insertions(+), 0 deletions(-)
+ create mode 100644 arch/mips/jz4740/pwm.c
+
+--- /dev/null
++++ b/arch/mips/jz4740/pwm.c
+@@ -0,0 +1,177 @@
++/*
++ * Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de>
++ * JZ4740 platform PWM support
++ *
++ * 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.
++ *
++ * You should have received a copy of the GNU General Public License along
++ * with this program; if not, write to the Free Software Foundation, Inc.,
++ * 675 Mass Ave, Cambridge, MA 02139, USA.
++ *
++ */
++
++#include <linux/kernel.h>
++
++#include <linux/clk.h>
++#include <linux/err.h>
++#include <linux/pwm.h>
++#include <linux/gpio.h>
++
++#include <asm/mach-jz4740/gpio.h>
++#include "timer.h"
++
++static struct clk *jz4740_pwm_clk;
++
++DEFINE_MUTEX(jz4740_pwm_mutex);
++
++struct pwm_device {
++ unsigned int id;
++ unsigned int gpio;
++ bool used;
++};
++
++static struct pwm_device jz4740_pwm_list[] = {
++ { 2, JZ_GPIO_PWM2, false },
++ { 3, JZ_GPIO_PWM3, false },
++ { 4, JZ_GPIO_PWM4, false },
++ { 5, JZ_GPIO_PWM5, false },
++ { 6, JZ_GPIO_PWM6, false },
++ { 7, JZ_GPIO_PWM7, false },
++};
++
++struct pwm_device *pwm_request(int id, const char *label)
++{
++ int ret = 0;
++ struct pwm_device *pwm;
++
++ if (id < 2 || id > 7 || !jz4740_pwm_clk)
++ return ERR_PTR(-ENODEV);
++
++ mutex_lock(&jz4740_pwm_mutex);
++
++ pwm = &jz4740_pwm_list[id - 2];
++ if (pwm->used)
++ ret = -EBUSY;
++ else
++ pwm->used = true;
++
++ mutex_unlock(&jz4740_pwm_mutex);
++
++ if (ret)
++ return ERR_PTR(ret);
++
++ ret = gpio_request(pwm->gpio, label);
++
++ if (ret) {
++ printk(KERN_ERR "Failed to request pwm gpio: %d\n", ret);
++ pwm->used = false;
++ return ERR_PTR(ret);
++ }
++
++ jz_gpio_set_function(pwm->gpio, JZ_GPIO_FUNC_PWM);
++
++ jz4740_timer_start(id);
++
++ return pwm;
++}
++
++void pwm_free(struct pwm_device *pwm)
++{
++ pwm_disable(pwm);
++ jz4740_timer_set_ctrl(pwm->id, 0);
++
++ jz_gpio_set_function(pwm->gpio, JZ_GPIO_FUNC_NONE);
++ gpio_free(pwm->gpio);
++
++ jz4740_timer_stop(pwm->id);
++
++ pwm->used = false;
++}
++
++int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns)
++{
++ unsigned long long tmp;
++ unsigned long period, duty;
++ unsigned int prescaler = 0;
++ unsigned int id = pwm->id;
++ uint16_t ctrl;
++ bool is_enabled;
++
++ if (duty_ns < 0 || duty_ns > period_ns)
++ return -EINVAL;
++
++ tmp = (unsigned long long)clk_get_rate(jz4740_pwm_clk) * period_ns;
++ do_div(tmp, 1000000000);
++ period = tmp;
++
++ while (period > 0xffff && prescaler < 6) {
++ period >>= 2;
++ ++prescaler;
++ }
++
++ if (prescaler == 6)
++ return -EINVAL;
++
++ tmp = (unsigned long long)period * duty_ns;
++ do_div(tmp, period_ns);
++ duty = period - tmp;
++
++ if (duty >= period)
++ duty = period - 1;
++
++ is_enabled = jz4740_timer_is_enabled(id);
++ if (is_enabled)
++ pwm_disable(pwm);
++
++ jz4740_timer_set_count(id, 0);
++ jz4740_timer_set_duty(id, duty);
++ jz4740_timer_set_period(id, period);
++
++ ctrl = JZ_TIMER_CTRL_PRESCALER(prescaler) | JZ_TIMER_CTRL_SRC_EXT |
++ JZ_TIMER_CTRL_PWM_ABBRUPT_SHUTDOWN;
++
++ jz4740_timer_set_ctrl(id, ctrl);
++
++ if (is_enabled)
++ pwm_enable(pwm);
++
++ return 0;
++}
++
++int pwm_enable(struct pwm_device *pwm)
++{
++ uint32_t ctrl = jz4740_timer_get_ctrl(pwm->id);
++
++ ctrl |= JZ_TIMER_CTRL_PWM_ENABLE;
++ jz4740_timer_set_ctrl(pwm->id, ctrl);
++ jz4740_timer_enable(pwm->id);
++
++ return 0;
++}
++
++void pwm_disable(struct pwm_device *pwm)
++{
++ uint32_t ctrl = jz4740_timer_get_ctrl(pwm->id);
++
++ ctrl &= ~JZ_TIMER_CTRL_PWM_ENABLE;
++ jz4740_timer_disable(pwm->id);
++ jz4740_timer_set_ctrl(pwm->id, ctrl);
++}
++
++static int __init jz4740_pwm_init(void)
++{
++ int ret = 0;
++
++ jz4740_pwm_clk = clk_get(NULL, "ext");
++
++ if (IS_ERR(jz4740_pwm_clk)) {
++ ret = PTR_ERR(jz4740_pwm_clk);
++ jz4740_pwm_clk = NULL;
++ }
++
++ return ret;
++}
++subsys_initcall(jz4740_pwm_init);