From mboxrd@z Thu Jan 1 00:00:00 1970 From: wellsk40@gmail.com (wellsk40 at gmail.com) Date: Tue, 3 Aug 2010 09:03:59 -0700 Subject: [PATCH 2/2] amba_pl022: Add support for amba peripheral clocking In-Reply-To: <1280851439-25468-1-git-send-email-wellsk40@gmail.com> References: <1280851439-25468-1-git-send-email-wellsk40@gmail.com> Message-ID: <1280851439-25468-3-git-send-email-wellsk40@gmail.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org From: Kevin Wells For register based accesses, enable the AMBA peripheral clock prior to a register access and disable it after a register access. The AMBA PCLK is disabled on probe and restored on remove. --- drivers/video/amba-clcd.c | 19 +++++++++++++++++++ 1 files changed, 19 insertions(+), 0 deletions(-) diff --git a/drivers/video/amba-clcd.c b/drivers/video/amba-clcd.c index 1c2c683..1d2fe32 100644 --- a/drivers/video/amba-clcd.c +++ b/drivers/video/amba-clcd.c @@ -65,6 +65,8 @@ static void clcdfb_disable(struct clcd_fb *fb) if (fb->board->disable) fb->board->disable(fb); + amba_pclk_enable(fb->dev); + val = readl(fb->regs + fb->off_cntl); if (val & CNTL_LCDPWR) { val &= ~CNTL_LCDPWR; @@ -77,6 +79,8 @@ static void clcdfb_disable(struct clcd_fb *fb) writel(val, fb->regs + fb->off_cntl); } + amba_pclk_disable(fb->dev); + /* * Disable CLCD clock source. */ @@ -96,6 +100,8 @@ static void clcdfb_enable(struct clcd_fb *fb, u32 cntl) clk_enable(fb->clk); } + amba_pclk_enable(fb->dev); + /* * Bring up by first enabling.. */ @@ -110,6 +116,8 @@ static void clcdfb_enable(struct clcd_fb *fb, u32 cntl) cntl |= CNTL_LCDPWR; writel(cntl, fb->regs + fb->off_cntl); + amba_pclk_disable(fb->dev); + /* * finally, enable the interface. */ @@ -217,6 +225,7 @@ static int clcdfb_set_par(struct fb_info *info) fb->board->decode(fb, ®s); clcdfb_disable(fb); + amba_pclk_disable(fb->dev); writel(regs.tim0, fb->regs + CLCD_TIM0); writel(regs.tim1, fb->regs + CLCD_TIM1); @@ -242,6 +251,8 @@ static int clcdfb_set_par(struct fb_info *info) readl(fb->regs + fb->off_ienb), readl(fb->regs + fb->off_cntl)); #endif + amba_pclk_disable(fb->dev); + return 0; } @@ -290,8 +301,10 @@ clcdfb_setcolreg(unsigned int regno, unsigned int red, unsigned int green, mask = 0xffff0000; } + amba_pclk_enable(fb->dev); val = readl(fb->regs + hw_reg) & mask; writel(val | newval, fb->regs + hw_reg); + amba_pclk_disable(fb->dev); } return regno > 255; @@ -492,6 +505,9 @@ static int clcdfb_probe(struct amba_device *dev, struct amba_id *id) ret = clcdfb_register(fb); if (ret == 0) { + /* Disable AMBA PCLK */ + amba_pclk_disable(dev); + amba_set_drvdata(dev, fb); goto out; } @@ -524,6 +540,9 @@ static int clcdfb_remove(struct amba_device *dev) amba_release_regions(dev); + /* Restore AMBA PCLK */ + amba_pclk_enable(dev); + return 0; } -- 1.7.1.1