ENGR00299746-3 imx: lcdif: add disp_axi clock handling for imx6sx

The display axi clock is a clock gating newly added on imx6sx.
It need to be enabled for lcdif/pxp/csi/pcie to work.
It should be set as a placeholder on other SoCs.

This patch also simplifies the sanity check for axi and pixel clock.

Signed-off-by: Sandor Yu <R01008@freescale.com>
Signed-off-by: Robby Cai <R63905@freescale.com>

1 files changed, 39 insertions, 4 deletions

diff --git a/drivers/video/mxsfb.c b/drivers/video/mxsfb.c
index 7b0304af8665..cbca5c65d2e4 100644
--- a/drivers/video/mxsfb.c
+++ b/drivers/video/mxsfb.c
@@ -187,7 +187,9 @@ struct mxsfb_info {
         struct platform_device *pdev;
         struct clk *clk_pix;
         struct clk *clk_axi;
+        struct clk *clk_disp_axi;
         bool clk_axi_enabled;
+        bool clk_disp_axi_enabled;
         void __iomem *base;     /* registers */
         unsigned allocated_size;
         int enabled;
@@ -234,8 +236,7 @@ static int mxsfb_unmap_videomem(struct fb_info *info);
 /* enable lcdif axi clock */
 static inline void clk_enable_axi(struct mxsfb_info *host)
 {
-        if (!host->clk_axi_enabled && host &&
-                host->clk_axi && !IS_ERR(host->clk_axi)) {
+        if (!host->clk_axi_enabled && (host->clk_axi != NULL)) {
                 clk_prepare_enable(host->clk_axi);
                 host->clk_axi_enabled = true;
         }
@@ -244,13 +245,30 @@ static inline void clk_enable_axi(struct mxsfb_info *host)
 /* disable lcdif axi clock */
 static inline void clk_disable_axi(struct mxsfb_info *host)
 {
-        if (host->clk_axi_enabled && host &&
-                host->clk_axi && !IS_ERR(host->clk_axi)) {
+        if (host->clk_axi_enabled && (host->clk_axi != NULL)) {
                 clk_disable_unprepare(host->clk_axi);
                 host->clk_axi_enabled = false;
         }
 }
 
+/* enable DISP axi clock */
+static inline void clk_enable_disp_axi(struct mxsfb_info *host)
+{
+        if (!host->clk_disp_axi_enabled && (host->clk_disp_axi != NULL)) {
+                clk_prepare_enable(host->clk_disp_axi);
+                host->clk_disp_axi_enabled = true;
+        }
+}
+
+/* disable DISP axi clock */
+static inline void clk_disable_disp_axi(struct mxsfb_info *host)
+{
+        if (host->clk_disp_axi_enabled && (host->clk_disp_axi != NULL)) {
+                clk_disable_unprepare(host->clk_disp_axi);
+                host->clk_disp_axi_enabled = false;
+        }
+}
+
 /* mask and shift depends on architecture */
 static inline u32 set_hsync_pulse_width(struct mxsfb_info *host, unsigned val)
 {
@@ -430,6 +448,7 @@ static void mxsfb_enable_controller(struct fb_info *fb_info)
         pm_runtime_get_sync(&host->pdev->dev);
 
         clk_enable_axi(host);
+        clk_enable_disp_axi(host);
 
         clk_prepare_enable(host->clk_pix);
         clk_set_rate(host->clk_pix, PICOS2KHZ(fb_info->var.pixclock) * 1000U);
@@ -464,6 +483,7 @@ static void mxsfb_disable_controller(struct fb_info *fb_info)
         dev_dbg(&host->pdev->dev, "%s\n", __func__);
 
         clk_enable_axi(host);
+        clk_enable_disp_axi(host);
         /*
          * Even if we disable the controller here, it will still continue
          * until its FIFOs are running out of data
@@ -505,6 +525,7 @@ static int mxsfb_set_par(struct fb_info *fb_info)
         int reenable = 0;
 
         clk_enable_axi(host);
+        clk_enable_disp_axi(host);
 
         dev_dbg(&host->pdev->dev, "%s\n", __func__);
         /*
@@ -726,6 +747,7 @@ static int mxsfb_blank(int blank, struct fb_info *fb_info)
                 if (host->enabled)
                         mxsfb_disable_controller(fb_info);
 
+                clk_disable_disp_axi(host);
                 clk_disable_axi(host);
                 break;
 
@@ -761,6 +783,7 @@ static int mxsfb_pan_display(struct fb_var_screeninfo *var,
         }
 
         clk_enable_axi(host);
+        clk_enable_disp_axi(host);
 
         offset = fb_info->fix.line_length * var->yoffset;
 
@@ -834,6 +857,7 @@ static int mxsfb_restore_mode(struct mxsfb_info *host)
         struct fb_videomode vmode;
 
         clk_enable_axi(host);
+        clk_enable_disp_axi(host);
 
         /* Only restore the mode when the controller is running */
         ctrl = readl(host->base + LCDC_CTRL);
@@ -1190,16 +1214,25 @@ static int mxsfb_probe(struct platform_device *pdev)
 
         host->clk_pix = devm_clk_get(&host->pdev->dev, "pix");
         if (IS_ERR(host->clk_pix)) {
+                host->clk_pix = NULL;
                 ret = PTR_ERR(host->clk_pix);
                 goto fb_release;
         }
 
         host->clk_axi = devm_clk_get(&host->pdev->dev, "axi");
         if (IS_ERR(host->clk_axi)) {
+                host->clk_axi = NULL;
                 ret = PTR_ERR(host->clk_axi);
                 goto fb_release;
         }
 
+        host->clk_disp_axi = devm_clk_get(&host->pdev->dev, "disp_axi");
+        if (IS_ERR(host->clk_disp_axi)) {
+                host->clk_disp_axi = NULL;
+                ret = PTR_ERR(host->clk_disp_axi);
+                goto fb_release;
+        }
+
         host->reg_lcd = devm_regulator_get(&pdev->dev, "lcd");
         if (IS_ERR(host->reg_lcd))
                 host->reg_lcd = NULL;
@@ -1274,12 +1307,14 @@ static void mxsfb_shutdown(struct platform_device *pdev)
         struct mxsfb_info *host = to_imxfb_host(fb_info);
 
         clk_enable_axi(host);
+        clk_enable_disp_axi(host);
         /*
          * Force stop the LCD controller as keeping it running during reboot
          * might interfere with the BootROM's boot mode pads sampling.
          */
         writel(CTRL_RUN, host->base + LCDC_CTRL + REG_CLR);
         writel(CTRL_MASTER, host->base + LCDC_CTRL + REG_CLR);
+        clk_disable_disp_axi(host);
         clk_disable_axi(host);
 }