[PATCH v2 2/5] fbdev: sa1100fb: make use of device clock
Dmitry Eremin-Solenikov
dbaryshkov at gmail.com
Sat Nov 16 17:07:27 EST 2013
Use per-device clock (instead of calling cpufreq_get(0), which can
return 0 if no cpu frequency driver is selected) to program timings.
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov at gmail.com>
---
drivers/video/sa1100fb.c | 24 +++++++++++++++++-------
drivers/video/sa1100fb.h | 1 +
2 files changed, 18 insertions(+), 7 deletions(-)
diff --git a/drivers/video/sa1100fb.c b/drivers/video/sa1100fb.c
index de76da0..05d1b37 100644
--- a/drivers/video/sa1100fb.c
+++ b/drivers/video/sa1100fb.c
@@ -178,6 +178,7 @@
#include <linux/dma-mapping.h>
#include <linux/mutex.h>
#include <linux/io.h>
+#include <linux/clk.h>
#include <video/sa1100fb.h>
@@ -413,9 +414,9 @@ sa1100fb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
var->transp.offset);
#ifdef CONFIG_CPU_FREQ
- dev_dbg(fbi->dev, "dma period = %d ps, clock = %d kHz\n",
+ dev_dbg(fbi->dev, "dma period = %d ps, clock = %ld kHz\n",
sa1100fb_display_dma_period(var),
- cpufreq_get(smp_processor_id()));
+ clk_get_rate(fbi->clk) / 1000);
#endif
return 0;
@@ -586,9 +587,10 @@ static struct fb_ops sa1100fb_ops = {
* Calculate the PCD value from the clock rate (in picoseconds).
* We take account of the PPCR clock setting.
*/
-static inline unsigned int get_pcd(unsigned int pixclock, unsigned int cpuclock)
+static inline unsigned int get_pcd(struct sa1100fb_info *fbi,
+ unsigned int pixclock)
{
- unsigned int pcd = cpuclock / 100;
+ unsigned int pcd = clk_get_rate(fbi->clk) / 100 / 1000;
pcd *= pixclock;
pcd /= 10000000;
@@ -667,7 +669,7 @@ static int sa1100fb_activate_var(struct fb_var_screeninfo *var, struct sa1100fb_
LCCR2_BegFrmDel(var->upper_margin) +
LCCR2_EndFrmDel(var->lower_margin);
- pcd = get_pcd(var->pixclock, cpufreq_get(0));
+ pcd = get_pcd(fbi, var->pixclock);
new_regs.lccr3 = LCCR3_PixClkDiv(pcd) | fbi->inf->lccr3 |
(var->sync & FB_SYNC_HOR_HIGH_ACT ? LCCR3_HorSnchH : LCCR3_HorSnchL) |
(var->sync & FB_SYNC_VERT_HIGH_ACT ? LCCR3_VrtSnchH : LCCR3_VrtSnchL);
@@ -1003,7 +1005,6 @@ sa1100fb_freq_transition(struct notifier_block *nb, unsigned long val,
void *data)
{
struct sa1100fb_info *fbi = TO_INF(nb, freq_transition);
- struct cpufreq_freqs *f = data;
u_int pcd;
switch (val) {
@@ -1012,7 +1013,7 @@ sa1100fb_freq_transition(struct notifier_block *nb, unsigned long val,
break;
case CPUFREQ_POSTCHANGE:
- pcd = get_pcd(fbi->fb.var.pixclock, f->new);
+ pcd = get_pcd(fbi, fbi->fb.var.pixclock);
fbi->reg_lccr3 = (fbi->reg_lccr3 & ~0xff) | LCCR3_PixClkDiv(pcd);
set_ctrlr_state(fbi, C_ENABLE_CLKCHANGE);
break;
@@ -1219,6 +1220,13 @@ static int sa1100fb_probe(struct platform_device *pdev)
if (!fbi)
goto failed;
+ fbi->clk = clk_get(&pdev->dev, NULL);
+ if (IS_ERR(fbi->clk)) {
+ ret = PTR_ERR(fbi->clk);
+ fbi->clk = NULL;
+ goto failed;
+ }
+
fbi->base = ioremap(res->start, resource_size(res));
if (!fbi->base)
goto failed;
@@ -1271,6 +1279,8 @@ static int sa1100fb_probe(struct platform_device *pdev)
failed:
if (fbi)
iounmap(fbi->base);
+ if (fbi->clk)
+ clk_put(fbi->clk);
kfree(fbi);
release_mem_region(res->start, resource_size(res));
return ret;
diff --git a/drivers/video/sa1100fb.h b/drivers/video/sa1100fb.h
index fc5d429..0139d13 100644
--- a/drivers/video/sa1100fb.h
+++ b/drivers/video/sa1100fb.h
@@ -68,6 +68,7 @@ struct sa1100fb_info {
#endif
const struct sa1100fb_mach_info *inf;
+ struct clk *clk;
};
#define TO_INF(ptr,member) container_of(ptr,struct sa1100fb_info,member)
--
1.8.4.2
More information about the linux-arm-kernel
mailing list