From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paul Walmsley Subject: [PATCH 3/3] ARM: OMAP2420: hwmod data/PM: use hwmod to block WFI when I2C active Date: Sun, 30 Dec 2012 11:28:31 -0700 Message-ID: <20121230182830.30526.5466.stgit@dusk.lan> References: <20121230182745.30526.47072.stgit@dusk.lan> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Return-path: Received: from utopia.booyaka.com ([74.50.51.50]:38199 "EHLO utopia.booyaka.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754795Ab2L3S25 (ORCPT ); Sun, 30 Dec 2012 13:28:57 -0500 In-Reply-To: <20121230182745.30526.47072.stgit@dusk.lan> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: Kevin Hilman Use the HWMOD_BLOCK_WFI flag in the hwmod data to prevent the MPU from entering WFI when the I2C devices are active. No idea why this is needed; this could certainly bear further investigation if anyone is interested. The objective here is to remove some custom code from the OMAP24xx PM code. Signed-off-by: Paul Walmsley Cc: Kevin Hilman --- arch/arm/mach-omap2/omap_hwmod_2420_data.c | 7 ++++++- arch/arm/mach-omap2/pm24xx.c | 13 ------------- 2 files changed, 6 insertions(+), 14 deletions(-) diff --git a/arch/arm/mach-omap2/omap_hwmod_2420_data.c b/arch/arm/mach-omap2/omap_hwmod_2420_data.c index b5efe58..6a764af 100644 --- a/arch/arm/mach-omap2/omap_hwmod_2420_data.c +++ b/arch/arm/mach-omap2/omap_hwmod_2420_data.c @@ -121,7 +121,12 @@ static struct omap_hwmod omap2420_i2c1_hwmod = { }, .class = &i2c_class, .dev_attr = &i2c_dev_attr, - .flags = HWMOD_16BIT_REG, + /* + * From mach-omap2/pm24xx.c: "Putting MPU into the WFI state + * while a transfer is active seems to cause the I2C block to + * timeout. Why? Good question." + */ + .flags = (HWMOD_16BIT_REG | HWMOD_BLOCK_WFI), }; /* I2C2 */ diff --git a/arch/arm/mach-omap2/pm24xx.c b/arch/arm/mach-omap2/pm24xx.c index 659a2f5..f69c701 100644 --- a/arch/arm/mach-omap2/pm24xx.c +++ b/arch/arm/mach-omap2/pm24xx.c @@ -139,14 +139,6 @@ no_sleep: return 0; } -static int omap2_i2c_active(void) -{ - u32 l; - - l = omap2_cm_read_mod_reg(CORE_MOD, CM_FCLKEN1); - return l & (OMAP2420_EN_I2C2_MASK | OMAP2420_EN_I2C1_MASK); -} - static int sti_console_enabled; static int omap2_allow_mpu_retention(void) @@ -171,11 +163,6 @@ static int omap2_allow_mpu_retention(void) static void omap2_enter_mpu_retention(void) { - /* Putting MPU into the WFI state while a transfer is active - * seems to cause the I2C block to timeout. Why? Good question. */ - if (omap2_i2c_active()) - return; - /* The peripherals seem not to be able to wake up the MPU when * it is in retention mode. */ if (omap2_allow_mpu_retention()) { From mboxrd@z Thu Jan 1 00:00:00 1970 From: paul@pwsan.com (Paul Walmsley) Date: Sun, 30 Dec 2012 11:28:31 -0700 Subject: [PATCH 3/3] ARM: OMAP2420: hwmod data/PM: use hwmod to block WFI when I2C active In-Reply-To: <20121230182745.30526.47072.stgit@dusk.lan> References: <20121230182745.30526.47072.stgit@dusk.lan> Message-ID: <20121230182830.30526.5466.stgit@dusk.lan> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Use the HWMOD_BLOCK_WFI flag in the hwmod data to prevent the MPU from entering WFI when the I2C devices are active. No idea why this is needed; this could certainly bear further investigation if anyone is interested. The objective here is to remove some custom code from the OMAP24xx PM code. Signed-off-by: Paul Walmsley Cc: Kevin Hilman --- arch/arm/mach-omap2/omap_hwmod_2420_data.c | 7 ++++++- arch/arm/mach-omap2/pm24xx.c | 13 ------------- 2 files changed, 6 insertions(+), 14 deletions(-) diff --git a/arch/arm/mach-omap2/omap_hwmod_2420_data.c b/arch/arm/mach-omap2/omap_hwmod_2420_data.c index b5efe58..6a764af 100644 --- a/arch/arm/mach-omap2/omap_hwmod_2420_data.c +++ b/arch/arm/mach-omap2/omap_hwmod_2420_data.c @@ -121,7 +121,12 @@ static struct omap_hwmod omap2420_i2c1_hwmod = { }, .class = &i2c_class, .dev_attr = &i2c_dev_attr, - .flags = HWMOD_16BIT_REG, + /* + * From mach-omap2/pm24xx.c: "Putting MPU into the WFI state + * while a transfer is active seems to cause the I2C block to + * timeout. Why? Good question." + */ + .flags = (HWMOD_16BIT_REG | HWMOD_BLOCK_WFI), }; /* I2C2 */ diff --git a/arch/arm/mach-omap2/pm24xx.c b/arch/arm/mach-omap2/pm24xx.c index 659a2f5..f69c701 100644 --- a/arch/arm/mach-omap2/pm24xx.c +++ b/arch/arm/mach-omap2/pm24xx.c @@ -139,14 +139,6 @@ no_sleep: return 0; } -static int omap2_i2c_active(void) -{ - u32 l; - - l = omap2_cm_read_mod_reg(CORE_MOD, CM_FCLKEN1); - return l & (OMAP2420_EN_I2C2_MASK | OMAP2420_EN_I2C1_MASK); -} - static int sti_console_enabled; static int omap2_allow_mpu_retention(void) @@ -171,11 +163,6 @@ static int omap2_allow_mpu_retention(void) static void omap2_enter_mpu_retention(void) { - /* Putting MPU into the WFI state while a transfer is active - * seems to cause the I2C block to timeout. Why? Good question. */ - if (omap2_i2c_active()) - return; - /* The peripherals seem not to be able to wake up the MPU when * it is in retention mode. */ if (omap2_allow_mpu_retention()) {