This patch sets and unsets is_sr_reset is appropriate places so that trying to enable smart reflex in a non-supported OMAP chip does not lead to unnecessary crash. Basically today if sr_enable fails, sr_disable will crash due to accessing sr registers when sr clocks are not turned on. By checking on is_sr_reset flag and setting and unsetting this flag appropriately this crash is fixed in this patch.
Signed-off-by: Thara Gopinath <[email protected]> --- arch/arm/mach-omap2/smartreflex.c | 31 +++++++++++++++++++++---------- 1 files changed, 21 insertions(+), 10 deletions(-) diff --git a/arch/arm/mach-omap2/smartreflex.c b/arch/arm/mach-omap2/smartreflex.c index 1d7d2e6..3f4b47b 100644 --- a/arch/arm/mach-omap2/smartreflex.c +++ b/arch/arm/mach-omap2/smartreflex.c @@ -115,9 +115,14 @@ static int sr_clk_enable(struct omap_sr *sr) { struct omap_smartreflex_data *pdata = sr->pdev->dev.platform_data; + if (!sr->is_sr_reset) + return 0; + if (pdata->device_enable) pdata->device_enable(sr->pdev); + sr->is_sr_reset = 0; + return 0; } @@ -125,6 +130,9 @@ static void sr_clk_disable(struct omap_sr *sr) { struct omap_smartreflex_data *pdata = sr->pdev->dev.platform_data; + if (sr->is_sr_reset) + return; + if (pdata->device_idle) pdata->device_idle(sr->pdev); @@ -308,7 +316,6 @@ static void sr_configure(struct omap_sr *sr) ERRCONFIG_MCUVALIDINTEN | ERRCONFIG_MCUVALIDINTST | ERRCONFIG_MCUBOUNDINTEN | ERRCONFIG_MCUBOUNDINTST)); } - sr->is_sr_reset = 0; } static void sr_start_vddautocomp(int srid) @@ -329,8 +336,7 @@ static void sr_start_vddautocomp(int srid) sr->is_autocomp_active = 1; if (!sr_class->enable(srid)) { sr->is_autocomp_active = 0; - if (sr->is_sr_reset == 1) - sr_clk_disable(sr); + sr_clk_disable(sr); } } @@ -350,8 +356,10 @@ static void sr_stop_vddautocomp(int srid) } if (sr->is_autocomp_active == 1) { - sr_class->disable(srid); - sr_clk_disable(sr); + if (!sr->is_sr_reset) { + sr_class->disable(srid); + sr_clk_disable(sr); + } sr->is_autocomp_active = 0; } } @@ -431,6 +439,11 @@ int sr_enable(int srid, unsigned long volt) /* Enable the clocks and configure SR */ sr_clk_enable(sr); + + /* Check if SR is already enabled. If yes do nothing */ + if (sr_read_reg(sr, SRCONFIG) & SRCONFIG_SRENABLE) + return true; + sr_configure(sr); sr_write_reg(sr, NVALUERECIPROCAL, nvalue_reciprocal); @@ -518,10 +531,8 @@ void omap_smartreflex_enable(int srid) } if (sr->is_autocomp_active == 1) { - if (sr->is_sr_reset == 1) { - if (!sr_class->enable(srid)) - sr_clk_disable(sr); - } + if (!sr_class->enable(srid)) + sr_clk_disable(sr); } } @@ -550,7 +561,7 @@ void omap_smartreflex_disable(int srid) } if (sr->is_autocomp_active == 1) { - if (sr->is_sr_reset == 0) { + if (!sr->is_sr_reset) { sr_class->disable(srid); /* Disable SR clk */ sr_clk_disable(sr); -- 1.7.0.rc1.33.g07cf0f -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
