From 9aadd70aed60b47e367e7a1a6b9068daba04fe05 Mon Sep 17 00:00:00 2001 From: Paul Walmsley Date: Tue, 6 Nov 2012 16:31:32 +0000 Subject: [PATCH] Revert "ARM: OMAP: convert I2C driver to PM QoS for MPU latency constraints" This reverts commit 3db11feffc1ad2ab9dea27789e6b5b3032827adc (ARM: OMAP: convert I2C driver to PM QoS for MPU latency constraints). This commit causes I2C timeouts to appear on several OMAP3430/3530-based boards: http://marc.info/?l=linux-arm-kernel&m=135071372426971&w=2 http://marc.info/?l=linux-arm-kernel&m=135067558415214&w=2 http://marc.info/?l=linux-arm-kernel&m=135216013608196&w=2 and appears to have been sent for merging before one of its prerequisites was merged: http://marc.info/?l=linux-arm-kernel&m=135219411617621&w=2 Signed-off-by: Paul Walmsley Acked-by: Jean Pihet Signed-off-by: Wolfram Sang --- arch/arm/plat-omap/i2c.c | 21 +++++++++++++++++++++ drivers/i2c/busses/i2c-omap.c | 32 ++++++++++++++------------------ include/linux/i2c-omap.h | 1 + 3 files changed, 36 insertions(+), 18 deletions(-) diff --git a/arch/arm/plat-omap/i2c.c b/arch/arm/plat-omap/i2c.c index a5683a84c6ee..6013831a043e 100644 --- a/arch/arm/plat-omap/i2c.c +++ b/arch/arm/plat-omap/i2c.c @@ -26,12 +26,14 @@ #include #include #include +#include #include #include #include #include #include +#include #include #define OMAP_I2C_SIZE 0x3f @@ -127,6 +129,16 @@ static inline int omap1_i2c_add_bus(int bus_id) #ifdef CONFIG_ARCH_OMAP2PLUS +/* + * XXX This function is a temporary compatibility wrapper - only + * needed until the I2C driver can be converted to call + * omap_pm_set_max_dev_wakeup_lat() and handle a return code. + */ +static void omap_pm_set_max_mpu_wakeup_lat_compat(struct device *dev, long t) +{ + omap_pm_set_max_mpu_wakeup_lat(dev, t); +} + static inline int omap2_i2c_add_bus(int bus_id) { int l; @@ -158,6 +170,15 @@ static inline int omap2_i2c_add_bus(int bus_id) dev_attr = (struct omap_i2c_dev_attr *)oh->dev_attr; pdata->flags = dev_attr->flags; + /* + * When waiting for completion of a i2c transfer, we need to + * set a wake up latency constraint for the MPU. This is to + * ensure quick enough wakeup from idle, when transfer + * completes. + * Only omap3 has support for constraints + */ + if (cpu_is_omap34xx()) + pdata->set_mpu_wkup_lat = omap_pm_set_max_mpu_wakeup_lat_compat; pdev = omap_device_build(name, bus_id, oh, pdata, sizeof(struct omap_i2c_bus_platform_data), NULL, 0, 0); diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c index db31eaed6ea5..0b0254312d21 100644 --- a/drivers/i2c/busses/i2c-omap.c +++ b/drivers/i2c/busses/i2c-omap.c @@ -43,7 +43,6 @@ #include #include #include -#include /* I2C controller revisions */ #define OMAP_I2C_OMAP1_REV_2 0x20 @@ -187,8 +186,9 @@ struct omap_i2c_dev { int reg_shift; /* bit shift for I2C register addresses */ struct completion cmd_complete; struct resource *ioarea; - u32 latency; /* maximum MPU wkup latency */ - struct pm_qos_request pm_qos_request; + u32 latency; /* maximum mpu wkup latency */ + void (*set_mpu_wkup_lat)(struct device *dev, + long latency); u32 speed; /* Speed of bus in kHz */ u32 dtrev; /* extra revision from DT */ u32 flags; @@ -494,7 +494,9 @@ static void omap_i2c_resize_fifo(struct omap_i2c_dev *dev, u8 size, bool is_rx) dev->b_hw = 1; /* Enable hardware fixes */ /* calculate wakeup latency constraint for MPU */ - dev->latency = (1000000 * dev->threshold) / (1000 * dev->speed / 8); + if (dev->set_mpu_wkup_lat != NULL) + dev->latency = (1000000 * dev->threshold) / + (1000 * dev->speed / 8); } /* @@ -629,16 +631,8 @@ omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) if (r < 0) goto out; - /* - * When waiting for completion of a i2c transfer, we need to - * set a wake up latency constraint for the MPU. This is to - * ensure quick enough wakeup from idle, when transfer - * completes. - */ - if (dev->latency) - pm_qos_add_request(&dev->pm_qos_request, - PM_QOS_CPU_DMA_LATENCY, - dev->latency); + if (dev->set_mpu_wkup_lat != NULL) + dev->set_mpu_wkup_lat(dev->dev, dev->latency); for (i = 0; i < num; i++) { r = omap_i2c_xfer_msg(adap, &msgs[i], (i == (num - 1))); @@ -646,8 +640,8 @@ omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) break; } - if (dev->latency) - pm_qos_remove_request(&dev->pm_qos_request); + if (dev->set_mpu_wkup_lat != NULL) + dev->set_mpu_wkup_lat(dev->dev, -1); if (r == 0) r = num; @@ -1104,6 +1098,7 @@ omap_i2c_probe(struct platform_device *pdev) } else if (pdata != NULL) { dev->speed = pdata->clkrate; dev->flags = pdata->flags; + dev->set_mpu_wkup_lat = pdata->set_mpu_wkup_lat; dev->dtrev = pdata->rev; } @@ -1159,8 +1154,9 @@ omap_i2c_probe(struct platform_device *pdev) dev->b_hw = 1; /* Enable hardware fixes */ /* calculate wakeup latency constraint for MPU */ - dev->latency = (1000000 * dev->fifo_size) / - (1000 * dev->speed / 8); + if (dev->set_mpu_wkup_lat != NULL) + dev->latency = (1000000 * dev->fifo_size) / + (1000 * dev->speed / 8); } /* reset ASAP, clearing any IRQs */ diff --git a/include/linux/i2c-omap.h b/include/linux/i2c-omap.h index df804ba73e0b..92a0dc75bc74 100644 --- a/include/linux/i2c-omap.h +++ b/include/linux/i2c-omap.h @@ -34,6 +34,7 @@ struct omap_i2c_bus_platform_data { u32 clkrate; u32 rev; u32 flags; + void (*set_mpu_wkup_lat)(struct device *dev, long set); }; #endif -- 2.30.2