[PATCH 3/7] [media] ir-rx51: use PWM framework instead of OMAP dmtimer

From: Ivaylo Dimitrov
Date: Sat May 07 2016 - 11:22:37 EST


Convert driver to use PWM framework instead of calling dmtimer functions
directly for PWM timer. Remove paragraph about writing to the Free Software
Foundation's mailing address while at it.

Signed-off-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@xxxxxxxxx>
---
arch/arm/mach-omap2/board-rx51-peripherals.c | 1 -
arch/arm/mach-omap2/pdata-quirks.c | 1 -
drivers/media/rc/ir-rx51.c | 85 ++++++++++++++--------------
include/linux/platform_data/media/ir-rx51.h | 2 -
4 files changed, 44 insertions(+), 45 deletions(-)

diff --git a/arch/arm/mach-omap2/board-rx51-peripherals.c b/arch/arm/mach-omap2/board-rx51-peripherals.c
index 9a70739..e487575 100644
--- a/arch/arm/mach-omap2/board-rx51-peripherals.c
+++ b/arch/arm/mach-omap2/board-rx51-peripherals.c
@@ -1242,7 +1242,6 @@ static struct pwm_omap_dmtimer_pdata __maybe_unused pwm_dmtimer_pdata = {
#if defined(CONFIG_IR_RX51) || defined(CONFIG_IR_RX51_MODULE)
static struct lirc_rx51_platform_data rx51_lirc_data = {
.set_max_mpu_wakeup_lat = omap_pm_set_max_mpu_wakeup_lat,
- .pwm_timer = 9, /* Use GPT 9 for CIR */
#if IS_ENABLED(CONFIG_OMAP_DM_TIMER)
.dmtimer = &pwm_dmtimer_pdata,
#endif
diff --git a/arch/arm/mach-omap2/pdata-quirks.c b/arch/arm/mach-omap2/pdata-quirks.c
index ea3a7d5..af65781 100644
--- a/arch/arm/mach-omap2/pdata-quirks.c
+++ b/arch/arm/mach-omap2/pdata-quirks.c
@@ -491,7 +491,6 @@ static struct pwm_omap_dmtimer_pdata pwm_dmtimer_pdata = {

static struct lirc_rx51_platform_data __maybe_unused rx51_lirc_data = {
.set_max_mpu_wakeup_lat = omap_pm_set_max_mpu_wakeup_lat,
- .pwm_timer = 9, /* Use GPT 9 for CIR */
#if IS_ENABLED(CONFIG_OMAP_DM_TIMER)
.dmtimer = &pwm_dmtimer_pdata,
#endif
diff --git a/drivers/media/rc/ir-rx51.c b/drivers/media/rc/ir-rx51.c
index da839c3..5096ef3 100644
--- a/drivers/media/rc/ir-rx51.c
+++ b/drivers/media/rc/ir-rx51.c
@@ -12,13 +12,7 @@
* 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, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- *
*/
-
#include <linux/clk.h>
#include <linux/module.h>
#include <linux/interrupt.h>
@@ -26,6 +20,7 @@
#include <linux/platform_device.h>
#include <linux/sched.h>
#include <linux/wait.h>
+#include <linux/pwm.h>

#include <media/lirc.h>
#include <media/lirc_dev.h>
@@ -43,7 +38,7 @@
#define TIMER_MAX_VALUE 0xffffffff

struct lirc_rx51 {
- pwm_omap_dmtimer *pwm_timer;
+ struct pwm_device *pwm;
pwm_omap_dmtimer *pulse_timer;
struct pwm_omap_dmtimer_pdata *dmtimer;
struct device *dev;
@@ -58,32 +53,28 @@ struct lirc_rx51 {
int wbuf[WBUF_LEN];
int wbuf_index;
unsigned long device_is_open;
- int pwm_timer_num;
};

static void lirc_rx51_on(struct lirc_rx51 *lirc_rx51)
{
- lirc_rx51->dmtimer->set_pwm(lirc_rx51->pwm_timer, 0, 1,
- PWM_OMAP_DMTIMER_TRIGGER_OVERFLOW_AND_COMPARE);
+ pwm_enable(lirc_rx51->pwm);
}

static void lirc_rx51_off(struct lirc_rx51 *lirc_rx51)
{
- lirc_rx51->dmtimer->set_pwm(lirc_rx51->pwm_timer, 0, 1,
- PWM_OMAP_DMTIMER_TRIGGER_NONE);
+ pwm_disable(lirc_rx51->pwm);
}

static int init_timing_params(struct lirc_rx51 *lirc_rx51)
{
- u32 load, match;
-
- load = -(lirc_rx51->fclk_khz * 1000 / lirc_rx51->freq);
- match = -(lirc_rx51->duty_cycle * -load / 100);
- lirc_rx51->dmtimer->set_load(lirc_rx51->pwm_timer, 1, load);
- lirc_rx51->dmtimer->set_match(lirc_rx51->pwm_timer, 1, match);
- lirc_rx51->dmtimer->write_counter(lirc_rx51->pwm_timer, TIMER_MAX_VALUE - 2);
- lirc_rx51->dmtimer->start(lirc_rx51->pwm_timer);
+ struct pwm_device *pwm = lirc_rx51->pwm;
+ int duty, period = DIV_ROUND_CLOSEST(NSEC_PER_SEC, lirc_rx51->freq);
+
+ duty = DIV_ROUND_CLOSEST(lirc_rx51->duty_cycle * period, 100);
lirc_rx51->dmtimer->set_int_enable(lirc_rx51->pulse_timer, 0);
+
+ pwm_config(pwm, duty, period);
+
lirc_rx51->dmtimer->start(lirc_rx51->pulse_timer);

lirc_rx51->match = 0;
@@ -165,7 +156,7 @@ end:
/* Stop TX here */
lirc_rx51_off(lirc_rx51);
lirc_rx51->wbuf_index = -1;
- lirc_rx51->dmtimer->stop(lirc_rx51->pwm_timer);
+
lirc_rx51->dmtimer->stop(lirc_rx51->pulse_timer);
lirc_rx51->dmtimer->set_int_enable(lirc_rx51->pulse_timer, 0);
wake_up_interruptible(&lirc_rx51->wqueue);
@@ -176,13 +167,13 @@ end:
static int lirc_rx51_init_port(struct lirc_rx51 *lirc_rx51)
{
struct clk *clk_fclk;
- int retval, pwm_timer = lirc_rx51->pwm_timer_num;
+ int retval;

- lirc_rx51->pwm_timer = lirc_rx51->dmtimer->request_specific(pwm_timer);
- if (lirc_rx51->pwm_timer == NULL) {
- dev_err(lirc_rx51->dev, ": Error requesting GPT%d timer\n",
- pwm_timer);
- return -EBUSY;
+ lirc_rx51->pwm = pwm_get(lirc_rx51->dev, NULL);
+ if (IS_ERR(lirc_rx51->pwm)) {
+ retval = PTR_ERR(lirc_rx51->pwm);
+ dev_err(lirc_rx51->dev, ": pwm_get failed: %d\n", retval);
+ return retval;
}

lirc_rx51->pulse_timer = lirc_rx51->dmtimer->request();
@@ -192,15 +183,11 @@ static int lirc_rx51_init_port(struct lirc_rx51 *lirc_rx51)
goto err1;
}

- lirc_rx51->dmtimer->set_source(lirc_rx51->pwm_timer,
- PWM_OMAP_DMTIMER_SRC_SYS_CLK);
lirc_rx51->dmtimer->set_source(lirc_rx51->pulse_timer,
PWM_OMAP_DMTIMER_SRC_SYS_CLK);
-
- lirc_rx51->dmtimer->enable(lirc_rx51->pwm_timer);
lirc_rx51->dmtimer->enable(lirc_rx51->pulse_timer);
-
- lirc_rx51->irq_num = lirc_rx51->dmtimer->get_irq(lirc_rx51->pulse_timer);
+ lirc_rx51->irq_num =
+ lirc_rx51->dmtimer->get_irq(lirc_rx51->pulse_timer);
retval = request_irq(lirc_rx51->irq_num, lirc_rx51_interrupt_handler,
IRQF_SHARED, "lirc_pulse_timer", lirc_rx51);
if (retval) {
@@ -208,7 +195,7 @@ static int lirc_rx51_init_port(struct lirc_rx51 *lirc_rx51)
goto err2;
}

- clk_fclk = lirc_rx51->dmtimer->get_fclk(lirc_rx51->pwm_timer);
+ clk_fclk = lirc_rx51->dmtimer->get_fclk(lirc_rx51->pulse_timer);
lirc_rx51->fclk_khz = clk_get_rate(clk_fclk) / 1000;

return 0;
@@ -216,7 +203,7 @@ static int lirc_rx51_init_port(struct lirc_rx51 *lirc_rx51)
err2:
lirc_rx51->dmtimer->free(lirc_rx51->pulse_timer);
err1:
- lirc_rx51->dmtimer->free(lirc_rx51->pwm_timer);
+ pwm_put(lirc_rx51->pwm);

return retval;
}
@@ -226,11 +213,10 @@ static int lirc_rx51_free_port(struct lirc_rx51 *lirc_rx51)
lirc_rx51->dmtimer->set_int_enable(lirc_rx51->pulse_timer, 0);
free_irq(lirc_rx51->irq_num, lirc_rx51);
lirc_rx51_off(lirc_rx51);
- lirc_rx51->dmtimer->disable(lirc_rx51->pwm_timer);
lirc_rx51->dmtimer->disable(lirc_rx51->pulse_timer);
- lirc_rx51->dmtimer->free(lirc_rx51->pwm_timer);
lirc_rx51->dmtimer->free(lirc_rx51->pulse_timer);
lirc_rx51->wbuf_index = -1;
+ pwm_put(lirc_rx51->pwm);

return 0;
}
@@ -387,7 +373,6 @@ static int lirc_rx51_release(struct inode *inode, struct file *file)
}

static struct lirc_rx51 lirc_rx51 = {
- .freq = 38000,
.duty_cycle = 50,
.wbuf_index = -1,
};
@@ -445,14 +430,34 @@ static int lirc_rx51_resume(struct platform_device *dev)

static int lirc_rx51_probe(struct platform_device *dev)
{
+ struct pwm_device *pwm;
+
lirc_rx51_driver.features = LIRC_RX51_DRIVER_FEATURES;
lirc_rx51.pdata = dev->dev.platform_data;
+
+ if (!lirc_rx51.pdata) {
+ dev_err(&dev->dev, "Platform Data is missing\n");
+ return -ENXIO;
+ }
+
if (!lirc_rx51.pdata->dmtimer) {
dev_err(&dev->dev, "no dmtimer?\n");
return -ENODEV;
}

- lirc_rx51.pwm_timer_num = lirc_rx51.pdata->pwm_timer;
+ pwm = pwm_get(&dev->dev, NULL);
+ if (IS_ERR(pwm)) {
+ int err = PTR_ERR(pwm);
+
+ if (err != -EPROBE_DEFER)
+ dev_err(&dev->dev, "pwm_get failed: %d\n", err);
+ return err;
+ }
+
+ /* Use default, in case userspace does not set the carrier */
+ lirc_rx51.freq = DIV_ROUND_CLOSEST(pwm_get_period(pwm), NSEC_PER_SEC);
+ pwm_put(pwm);
+
lirc_rx51.dmtimer = lirc_rx51.pdata->dmtimer;
lirc_rx51.dev = &dev->dev;
lirc_rx51_driver.dev = &dev->dev;
@@ -464,8 +469,6 @@ static int lirc_rx51_probe(struct platform_device *dev)
lirc_rx51_driver.minor);
return lirc_rx51_driver.minor;
}
- dev_info(lirc_rx51.dev, "registration ok, minor: %d, pwm: %d\n",
- lirc_rx51_driver.minor, lirc_rx51.pwm_timer_num);

return 0;
}
diff --git a/include/linux/platform_data/media/ir-rx51.h b/include/linux/platform_data/media/ir-rx51.h
index 3038120..6acf22d 100644
--- a/include/linux/platform_data/media/ir-rx51.h
+++ b/include/linux/platform_data/media/ir-rx51.h
@@ -2,8 +2,6 @@
#define _LIRC_RX51_H

struct lirc_rx51_platform_data {
- int pwm_timer;
-
int(*set_max_mpu_wakeup_lat)(struct device *dev, long t);
struct pwm_omap_dmtimer_pdata *dmtimer;
};
--
1.9.1