From mboxrd@z Thu Jan 1 00:00:00 1970 From: Shubhrajyoti D Subject: [PATCHV3 4/4] OMAP: I2C: I2C register restore only if context is lost Date: Thu, 21 Jul 2011 19:23:01 +0530 Message-ID: <1311256381-25548-5-git-send-email-shubhrajyoti@ti.com> References: <1311256381-25548-1-git-send-email-shubhrajyoti@ti.com> Mime-Version: 1.0 Content-Type: text/plain Return-path: In-Reply-To: <1311256381-25548-1-git-send-email-shubhrajyoti-l0cyMroinI0@public.gmane.org> Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: linux-omap-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Cc: linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, khilman-l0cyMroinI0@public.gmane.org, rnayak-l0cyMroinI0@public.gmane.org, balajitk-l0cyMroinI0@public.gmane.org, santosh.shilimkar-l0cyMroinI0@public.gmane.org, Shubhrajyoti D List-Id: linux-i2c@vger.kernel.org Currently i2c register restore is done always. Adding conditional restore. The i2c register restore is done only if the context is lost. Acked-by: Santosh Shilimkar Signed-off-by: Shubhrajyoti D --- drivers/i2c/busses/i2c-omap.c | 24 +++++++++++++++++------- 1 files changed, 17 insertions(+), 7 deletions(-) diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c index 75bb62d..dffdbfd 100644 --- a/drivers/i2c/busses/i2c-omap.c +++ b/drivers/i2c/busses/i2c-omap.c @@ -40,6 +40,7 @@ #include #include #include +#include /* I2C controller revisions */ #define OMAP_I2C_OMAP1_REV_2 0x20 @@ -200,6 +201,7 @@ struct omap_i2c_dev { u16 syscstate; u16 westate; u16 errata; + u32 dev_lost_count; }; const static u8 reg_map_ip_v1[] = { @@ -260,6 +262,17 @@ static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg) (i2c_dev->regs[reg] << i2c_dev->reg_shift)); } +static void omap_i2c_restore(struct omap_i2c_dev *dev) +{ + omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0); + omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, dev->pscstate); + omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, dev->scllstate); + omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, dev->sclhstate); + omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, dev->bufstate); + omap_i2c_write_reg(dev, OMAP_I2C_WE_REG, dev->westate); + omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN); +} + static void omap_i2c_unidle(struct omap_i2c_dev *dev) { struct platform_device *pdev; @@ -273,13 +286,9 @@ static void omap_i2c_unidle(struct omap_i2c_dev *dev) pm_runtime_get_sync(&pdev->dev); if (pdata->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) { - omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0); - omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, dev->pscstate); - omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, dev->scllstate); - omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, dev->sclhstate); - omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, dev->bufstate); - omap_i2c_write_reg(dev, OMAP_I2C_WE_REG, dev->westate); - omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN); + u32 loss_cnt = omap_device_get_context_loss_count(pdev); + if (dev->dev_lost_count != loss_cnt) + omap_i2c_restore(dev); } dev->idle = 0; @@ -318,6 +327,7 @@ static void omap_i2c_idle(struct omap_i2c_dev *dev) } dev->idle = 1; + dev->dev_lost_count = omap_device_get_context_loss_count(pdev); pm_runtime_put_sync(&pdev->dev); } -- 1.7.1