[PATCH 07/10] drm/mxsfb: Update mxsfb to support LCD reset

From: Robert Chiras
Date: Wed Jun 26 2019 - 09:33:03 EST


The eLCDIF controller has control pin for the external LCD reset pin.
Add support for it and assert this pin in enable and de-assert it in
disable.

Signed-off-by: Robert Chiras <robert.chiras@xxxxxxx>
---
drivers/gpu/drm/mxsfb/mxsfb_crtc.c | 10 ++++++++--
drivers/gpu/drm/mxsfb/mxsfb_regs.h | 1 +
2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/mxsfb/mxsfb_crtc.c b/drivers/gpu/drm/mxsfb/mxsfb_crtc.c
index e48396d..d9429fc 100644
--- a/drivers/gpu/drm/mxsfb/mxsfb_crtc.c
+++ b/drivers/gpu/drm/mxsfb/mxsfb_crtc.c
@@ -222,9 +222,12 @@ static void mxsfb_enable_controller(struct mxsfb_drm_private *mxsfb)
clk_prepare_enable(mxsfb->clk_disp_axi);
clk_prepare_enable(mxsfb->clk);

- if (mxsfb->devdata->ipversion >= 4)
+ if (mxsfb->devdata->ipversion >= 4) {
writel(CTRL2_OUTSTANDING_REQS__REQ_16,
mxsfb->base + LCDC_V4_CTRL2 + REG_SET);
+ /* Assert LCD Reset bit */
+ writel(CTRL2_LCD_RESET, mxsfb->base + LCDC_V4_CTRL2 + REG_SET);
+ }

/* If it was disabled, re-enable the mode again */
writel(CTRL_DOTCLK_MODE, mxsfb->base + LCDC_CTRL + REG_SET);
@@ -242,9 +245,12 @@ static void mxsfb_disable_controller(struct mxsfb_drm_private *mxsfb)
{
u32 reg;

- if (mxsfb->devdata->ipversion >= 4)
+ if (mxsfb->devdata->ipversion >= 4) {
writel(CTRL2_OUTSTANDING_REQS(0x7),
mxsfb->base + LCDC_V4_CTRL2 + REG_CLR);
+ /* De-assert LCD Reset bit */
+ writel(CTRL2_LCD_RESET, mxsfb->base + LCDC_V4_CTRL2 + REG_CLR);
+ }

writel(CTRL_RUN, mxsfb->base + LCDC_CTRL + REG_CLR);

diff --git a/drivers/gpu/drm/mxsfb/mxsfb_regs.h b/drivers/gpu/drm/mxsfb/mxsfb_regs.h
index 9ee0d3c7..2583a69 100644
--- a/drivers/gpu/drm/mxsfb/mxsfb_regs.h
+++ b/drivers/gpu/drm/mxsfb/mxsfb_regs.h
@@ -87,6 +87,7 @@
#define CTRL2_OUTSTANDING_REQS(x) REG_PUT((x), 23, 21)
#define CTRL2_ODD_LINE_PATTERN(x) REG_PUT((x), 18, 16)
#define CTRL2_EVEN_LINE_PATTERN(x) REG_PUT((x), 14, 12)
+#define CTRL2_LCD_RESET BIT(0)

#define TRANSFER_COUNT_SET_VCOUNT(x) (((x) & 0xffff) << 16)
#define TRANSFER_COUNT_GET_VCOUNT(x) (((x) >> 16) & 0xffff)
--
2.7.4