From 83bce1182d983be01f3247f974654cdac5690436 Mon Sep 17 00:00:00 2001 From: Jon Medhurst Date: Fri, 14 Jun 2013 18:30:08 +0100 Subject: [PATCH] ARM HDLCD: Fix clock initialisation sequence This reworks HDLCD initialisation to mirror how CLCD does this, in particular to prepare the clock immediately after it has been got which ensures that we don't try and enable clocks before they were prepared, e.g. in the former clk_enable after register_framebuffer(). The reason this issue wasn't noticed before is that we have been setting CONFIG_FRAMEBUFFER_CONSOLE and this caused register_framebuffer() to trigger the creation of a console which calls hdlcd_set_par(), which in turn was preparing and enabling the clock. Signed-off-by: Jon Medhurst --- drivers/video/arm-hdlcd.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/drivers/video/arm-hdlcd.c b/drivers/video/arm-hdlcd.c index f9c4e7490c05..cfd631e3dc52 100644 --- a/drivers/video/arm-hdlcd.c +++ b/drivers/video/arm-hdlcd.c @@ -289,7 +289,6 @@ static int hdlcd_set_par(struct fb_info *info) WRITE_HDLCD_REG(HDLCD_REG_GREEN_SELECT, ((hdlcd->fb.var.green.length & 0xf) << 8) | hdlcd->fb.var.green.offset); WRITE_HDLCD_REG(HDLCD_REG_BLUE_SELECT, ((hdlcd->fb.var.blue.length & 0xf) << 8) | hdlcd->fb.var.blue.offset); - clk_prepare(hdlcd->clk); clk_set_rate(hdlcd->clk, (1000000000 / hdlcd->fb.var.pixclock) * 1000); clk_enable(hdlcd->clk); @@ -481,6 +480,10 @@ static int hdlcd_setup(struct hdlcd_device *hdlcd) return PTR_ERR(hdlcd->clk); } + err = clk_prepare(hdlcd->clk); + if (err) + goto clk_prepare_err; + hdlcd->base = ioremap_nocache(hdlcd->fb.fix.mmio_start, hdlcd->fb.fix.mmio_len); if (!hdlcd->base) { dev_err(hdlcd->dev, "HDLCD: unable to map registers\n"); @@ -572,9 +575,9 @@ static int hdlcd_setup(struct hdlcd_device *hdlcd) /* Ensure interrupts are disabled */ WRITE_HDLCD_REG(HDLCD_REG_INT_MASK, 0); #endif + fb_set_var(&hdlcd->fb, &hdlcd->fb.var); + if (!register_framebuffer(&hdlcd->fb)) { - fb_set_var(&hdlcd->fb, &hdlcd->fb.var); - clk_enable(hdlcd->clk); return 0; } @@ -586,6 +589,8 @@ setup_err: kmalloc_err: kfree(hdlcd->fb.pseudo_palette); remap_err: + clk_unprepare(hdlcd->clk); +clk_prepare_err: clk_put(hdlcd->clk); return err; } -- 2.34.1