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| author | Bartosz Golaszewski <bgolaszewski@baylibre.com> | 2018-01-22 15:42:58 +0100 |
|---|---|---|
| committer | Wolfram Sang <wsa@the-dreams.de> | 2018-01-24 07:14:59 +0100 |
| commit | 19cfcafd7f0fa7a672f0ac5146e2ff38594497b0 (patch) | |
| tree | b052f7a036c236bdf70674bef6a60671752df124 /drivers/i2c/busses | |
| parent | 5bacb56b2b56283ab26fea9e15f06ebe27afbe3d (diff) | |
| download | linux-19cfcafd7f0fa7a672f0ac5146e2ff38594497b0.tar.gz linux-19cfcafd7f0fa7a672f0ac5146e2ff38594497b0.tar.bz2 linux-19cfcafd7f0fa7a672f0ac5146e2ff38594497b0.zip | |
i2c: davinci: fix the cpufreq transition
i2c_davinci_cpufreq_transition() is implemented in a way that will
block if it ever gets called while no transfer is in progress.
Not only that, but reinit_completion() is never called for xfr_complete.
Use the fact that cpufreq uses an srcu_notifier (running in process
context) for transitions and that the bus_lock is taken during the call
to master_xfer() and simplify the code by removing the transfer
completion entirely and protecting i2c_davinci_cpufreq_transition()
with i2c_lock/unlock_adapter().
Reported-by: David Lechner <david@lechnology.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Sekhar Nori <nsekhar@ti.com>
Tested-by: David Lechner <david@lechnology.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Diffstat (limited to 'drivers/i2c/busses')
| -rw-r--r-- | drivers/i2c/busses/i2c-davinci.c | 12 |
1 files changed, 4 insertions, 8 deletions
diff --git a/drivers/i2c/busses/i2c-davinci.c b/drivers/i2c/busses/i2c-davinci.c index cb24a3ffdfa2..75d6ab177055 100644 --- a/drivers/i2c/busses/i2c-davinci.c +++ b/drivers/i2c/busses/i2c-davinci.c @@ -139,7 +139,6 @@ struct davinci_i2c_dev { u8 terminate; struct i2c_adapter adapter; #ifdef CONFIG_CPU_FREQ - struct completion xfr_complete; struct notifier_block freq_transition; #endif struct davinci_i2c_platform_data *pdata; @@ -567,9 +566,6 @@ i2c_davinci_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) } ret = num; -#ifdef CONFIG_CPU_FREQ - complete(&dev->xfr_complete); -#endif out: pm_runtime_mark_last_busy(dev->dev); @@ -717,13 +713,15 @@ static int i2c_davinci_cpufreq_transition(struct notifier_block *nb, struct davinci_i2c_dev *dev; dev = container_of(nb, struct davinci_i2c_dev, freq_transition); + + i2c_lock_adapter(&dev->adapter); if (val == CPUFREQ_PRECHANGE) { - wait_for_completion(&dev->xfr_complete); davinci_i2c_reset_ctrl(dev, 0); } else if (val == CPUFREQ_POSTCHANGE) { i2c_davinci_calc_clk_dividers(dev); davinci_i2c_reset_ctrl(dev, 1); } + i2c_unlock_adapter(&dev->adapter); return 0; } @@ -790,9 +788,7 @@ static int davinci_i2c_probe(struct platform_device *pdev) } init_completion(&dev->cmd_complete); -#ifdef CONFIG_CPU_FREQ - init_completion(&dev->xfr_complete); -#endif + dev->dev = &pdev->dev; dev->irq = irq; dev->pdata = dev_get_platdata(&pdev->dev); |