From 06151158f2da4764479b4ec01688dc4bade6ce9d Mon Sep 17 00:00:00 2001 From: "Stanley.Miao" Date: Thu, 29 Jan 2009 08:57:12 -0800 Subject: ARM: OMAP: Fix McBSP spin_lock deadlock A spin_lock deadlock will occur when omap_mcbsp_request() is invoked. omap_mcbsp_request() \- clk_enable(mcbsp->clk) [takes and holds clockfw_lock] \- omap2_clk_enable() \- _omap2_clk_enable() \- omap_mcbsp_clk_enable() \- clk_enable(child clock) [tries for clockfw_lock again] mcbsp_clk is a virtual clock and it comprises several child clocks. when enable mcbsp_clk in omap_mcbsp_request(), the enable function of mcbsp_clk will enable its child clocks, then the deadlock occurs. The solution is to remove the virtual clock and enable these child clocks in omap_mcbsp_request() directly. Signed-off-by: Stanley.Miao Signed-off-by: Tony Lindgren --- arch/arm/mach-omap1/mcbsp.c | 98 +++++---------------------------------------- 1 file changed, 10 insertions(+), 88 deletions(-) (limited to 'arch/arm/mach-omap1/mcbsp.c') diff --git a/arch/arm/mach-omap1/mcbsp.c b/arch/arm/mach-omap1/mcbsp.c index ca7a0cc1707c..575ba31295cf 100644 --- a/arch/arm/mach-omap1/mcbsp.c +++ b/arch/arm/mach-omap1/mcbsp.c @@ -28,81 +28,8 @@ #define DPS_RSTCT2_PER_EN (1 << 0) #define DSP_RSTCT2_WD_PER_EN (1 << 1) -struct mcbsp_internal_clk { - struct clk clk; - struct clk **childs; - int n_childs; -}; - #if defined(CONFIG_ARCH_OMAP15XX) || defined(CONFIG_ARCH_OMAP16XX) -static void omap_mcbsp_clk_init(struct mcbsp_internal_clk *mclk) -{ - const char *clk_names[] = { "dsp_ck", "api_ck", "dspxor_ck" }; - int i; - - mclk->n_childs = ARRAY_SIZE(clk_names); - mclk->childs = kzalloc(mclk->n_childs * sizeof(struct clk *), - GFP_KERNEL); - - for (i = 0; i < mclk->n_childs; i++) { - /* We fake a platform device to get correct device id */ - struct platform_device pdev; - - pdev.dev.bus = &platform_bus_type; - pdev.id = mclk->clk.id; - mclk->childs[i] = clk_get(&pdev.dev, clk_names[i]); - if (IS_ERR(mclk->childs[i])) - printk(KERN_ERR "Could not get clock %s (%d).\n", - clk_names[i], mclk->clk.id); - } -} - -static int omap_mcbsp_clk_enable(struct clk *clk) -{ - struct mcbsp_internal_clk *mclk = container_of(clk, - struct mcbsp_internal_clk, clk); - int i; - - for (i = 0; i < mclk->n_childs; i++) - clk_enable(mclk->childs[i]); - return 0; -} - -static void omap_mcbsp_clk_disable(struct clk *clk) -{ - struct mcbsp_internal_clk *mclk = container_of(clk, - struct mcbsp_internal_clk, clk); - int i; - - for (i = 0; i < mclk->n_childs; i++) - clk_disable(mclk->childs[i]); -} - -static struct mcbsp_internal_clk omap_mcbsp_clks[] = { - { - .clk = { - .name = "mcbsp_clk", - .id = 1, - .enable = omap_mcbsp_clk_enable, - .disable = omap_mcbsp_clk_disable, - }, - }, - { - .clk = { - .name = "mcbsp_clk", - .id = 3, - .enable = omap_mcbsp_clk_enable, - .disable = omap_mcbsp_clk_disable, - }, - }, -}; - -#define omap_mcbsp_clks_size ARRAY_SIZE(omap_mcbsp_clks) -#else -#define omap_mcbsp_clks_size 0 -static struct mcbsp_internal_clk __initdata *omap_mcbsp_clks; -static inline void omap_mcbsp_clk_init(struct mcbsp_internal_clk *mclk) -{ } +const char *clk_names[] = { "dsp_ck", "api_ck", "dspxor_ck" }; #endif static void omap1_mcbsp_request(unsigned int id) @@ -167,8 +94,9 @@ static struct omap_mcbsp_platform_data omap15xx_mcbsp_pdata[] = { .rx_irq = INT_McBSP1RX, .tx_irq = INT_McBSP1TX, .ops = &omap1_mcbsp_ops, - .clk_name = "mcbsp_clk", - }, + .clk_names = clk_names, + .num_clks = 3, + }, { .phys_base = OMAP1510_MCBSP2_BASE, .dma_rx_sync = OMAP_DMA_MCBSP2_RX, @@ -184,7 +112,8 @@ static struct omap_mcbsp_platform_data omap15xx_mcbsp_pdata[] = { .rx_irq = INT_McBSP3RX, .tx_irq = INT_McBSP3TX, .ops = &omap1_mcbsp_ops, - .clk_name = "mcbsp_clk", + .clk_names = clk_names, + .num_clks = 3, }, }; #define OMAP15XX_MCBSP_PDATA_SZ ARRAY_SIZE(omap15xx_mcbsp_pdata) @@ -202,7 +131,8 @@ static struct omap_mcbsp_platform_data omap16xx_mcbsp_pdata[] = { .rx_irq = INT_McBSP1RX, .tx_irq = INT_McBSP1TX, .ops = &omap1_mcbsp_ops, - .clk_name = "mcbsp_clk", + .clk_names = clk_names, + .num_clks = 3, }, { .phys_base = OMAP1610_MCBSP2_BASE, @@ -219,7 +149,8 @@ static struct omap_mcbsp_platform_data omap16xx_mcbsp_pdata[] = { .rx_irq = INT_McBSP3RX, .tx_irq = INT_McBSP3TX, .ops = &omap1_mcbsp_ops, - .clk_name = "mcbsp_clk", + .clk_names = clk_names, + .num_clks = 3, }, }; #define OMAP16XX_MCBSP_PDATA_SZ ARRAY_SIZE(omap16xx_mcbsp_pdata) @@ -230,15 +161,6 @@ static struct omap_mcbsp_platform_data omap16xx_mcbsp_pdata[] = { int __init omap1_mcbsp_init(void) { - int i; - - for (i = 0; i < omap_mcbsp_clks_size; i++) { - if (cpu_is_omap15xx() || cpu_is_omap16xx()) { - omap_mcbsp_clk_init(&omap_mcbsp_clks[i]); - clk_register(&omap_mcbsp_clks[i].clk); - } - } - if (cpu_is_omap730()) omap_mcbsp_count = OMAP730_MCBSP_PDATA_SZ; if (cpu_is_omap15xx()) -- cgit v1.2.3