This patch implements fb_blank() for the glamo-fb driver, which switches off
the pixel clock (DCLK) for power saving.
We currently delay the actual pixel clock switch until we enter
FB_BLANK_POWERDOWN, since the backlight fade is slow and we don't want the
user to see artefacts on the screen while the backlight is fading out.
So since the X server first sends FB_BLANK_{V,H}SYNC_SUSPEND, we start the
backlight fade here, and only once we get FB_BLANK_POWERDOWN the pixel clock is
disabled.
There are no measurements yet, but the power savings should be double, since
there is no longer any generation of the high-frequency LCM signals, and
there are no video-related SDRAM accesses anymore.
Signed-off-by: Harald Welte <[EMAIL PROTECTED]>
---
drivers/mfd/glamo/glamo-core.c | 32 ++++++++++++++++++++++++++++++++
drivers/mfd/glamo/glamo-core.h | 6 ++++++
drivers/mfd/glamo/glamo-fb.c | 29 ++++++++++++++++++++++++++++-
3 files changed, 66 insertions(+), 1 deletions(-)
diff --git a/drivers/mfd/glamo/glamo-core.c b/drivers/mfd/glamo/glamo-core.c
index 2619c5f..58ee3e2 100644
--- a/drivers/mfd/glamo/glamo-core.c
+++ b/drivers/mfd/glamo/glamo-core.c
@@ -524,6 +524,38 @@ int glamo_engine_disable(struct glamo_core *glamo, enum
glamo_engine engine)
}
EXPORT_SYMBOL_GPL(glamo_engine_disable);
+static const u_int16_t engine_clock_regs[__NUM_GLAMO_ENGINES] = {
+ [GLAMO_ENGINE_LCD] = GLAMO_REG_CLOCK_LCD,
+ [GLAMO_ENGINE_MMC] = GLAMO_REG_CLOCK_MMC,
+ [GLAMO_ENGINE_ISP] = GLAMO_REG_CLOCK_ISP,
+ [GLAMO_ENGINE_JPEG] = GLAMO_REG_CLOCK_JPEG,
+ [GLAMO_ENGINE_3D] = GLAMO_REG_CLOCK_3D,
+ [GLAMO_ENGINE_2D] = GLAMO_REG_CLOCK_2D,
+ [GLAMO_ENGINE_MPEG_ENC] = GLAMO_REG_CLOCK_MPEG,
+ [GLAMO_ENGINE_MPEG_DEC] = GLAMO_REG_CLOCK_MPEG,
+};
+
+void glamo_engine_clkreg_set(struct glamo_core *glamo,
+ enum glamo_engine engine,
+ u_int16_t mask, u_int16_t val)
+{
+ reg_set_bit_mask(glamo, engine_clock_regs[engine], mask, val);
+}
+EXPORT_SYMBOL_GPL(glamo_engine_clkreg_set);
+
+u_int16_t glamo_engine_clkreg_get(struct glamo_core *glamo,
+ enum glamo_engine engine)
+{
+ u_int16_t val;
+
+ spin_lock(&glamo->lock);
+ val = __reg_read(glamo, engine_clock_regs[engine]);
+ spin_unlock(&glamo->lock);
+
+ return val;
+}
+EXPORT_SYMBOL_GPL(glamo_engine_clkreg_get);
+
struct glamo_script reset_regs[] = {
[GLAMO_ENGINE_LCD] = {
GLAMO_REG_CLOCK_LCD, GLAMO_CLOCK_LCD_RESET
diff --git a/drivers/mfd/glamo/glamo-core.h b/drivers/mfd/glamo/glamo-core.h
index ac5eacf..fb5f0f6 100644
--- a/drivers/mfd/glamo/glamo-core.h
+++ b/drivers/mfd/glamo/glamo-core.h
@@ -98,4 +98,10 @@ void glamo_engine_reset(struct glamo_core *glamo, enum
glamo_engine engine);
int glamo_engine_reclock(struct glamo_core *glamo,
enum glamo_engine engine, int ps);
+void glamo_engine_clkreg_set(struct glamo_core *glamo,
+ enum glamo_engine engine,
+ u_int16_t mask, u_int16_t val);
+
+u_int16_t glamo_engine_clkreg_get(struct glamo_core *glamo,
+ enum glamo_engine engine);
#endif /* __GLAMO_CORE_H */
diff --git a/drivers/mfd/glamo/glamo-fb.c b/drivers/mfd/glamo/glamo-fb.c
index 8f5d6b1..fe1aa3e 100644
--- a/drivers/mfd/glamo/glamo-fb.c
+++ b/drivers/mfd/glamo/glamo-fb.c
@@ -420,7 +420,34 @@ static int glamofb_set_par(struct fb_info *info)
static int glamofb_blank(int blank_mode, struct fb_info *info)
{
- /* FIXME */
+ struct glamofb_handle *gfb = info->par;
+ struct glamo_core *gcore = gfb->mach_info->glamo;
+
+ dev_dbg(gfb->dev, "glamofb_blank(%u)\n", blank_mode);
+
+ switch (blank_mode) {
+ case FB_BLANK_VSYNC_SUSPEND:
+ case FB_BLANK_HSYNC_SUSPEND:
+ /* FIXME: add pdata hook/flag to indicate whether
+ * we should already switch off pixel clock here */
+ break;
+ case FB_BLANK_POWERDOWN:
+ /* disable the pixel clock */
+ glamo_engine_clkreg_set(gcore, GLAMO_ENGINE_LCD,
+ GLAMO_CLOCK_LCD_EN_DCLK, 0);
+ break;
+ case FB_BLANK_UNBLANK:
+ case FB_BLANK_NORMAL:
+ /* enable the pixel clock */
+ glamo_engine_clkreg_set(gcore, GLAMO_ENGINE_LCD,
+ GLAMO_CLOCK_LCD_EN_DCLK,
+ GLAMO_CLOCK_LCD_EN_DCLK);
+ break;
+ }
+
+ /* FIXME: once we have proper clock management in glamo-core,
+ * we can determine if other units need MCLK1 or the PLL, and
+ * disable it if not used. */
return 0;
}
--
1.5.6.5
--
- Harald Welte <[EMAIL PROTECTED]> http://openmoko.org/
============================================================================
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