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53 lines
1.7 KiB
Diff
53 lines
1.7 KiB
Diff
From 97db2ca4485dc7b10b8382832befe607ade59a6b Mon Sep 17 00:00:00 2001
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From: Dong Aisheng <aisheng.dong@nxp.com>
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Date: Sat, 26 Jan 2019 17:51:59 +0800
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Subject: [PATCH] i2c: imx: fix system hang due to access i2c registers without
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clock
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Currently, i2c_imx_bus_busy in i2c_imx_xfer is called before
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pm_runtime_get which means the clocks are still not enabled.
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This will cause a hang on IMX as IMX requires accessing registers
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with clocks.
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So let's change the order to ensure the clocks are enabled before
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accessing registers. This is also a more safe way to access registers,
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suppose shouldn't affect other platforms.
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Fixes: 4a6ebf1c125c ("i2c: imx: add workaround for erratum ERR010027")
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Reviewed-by: Biwen Li <biwen.li@nxp.com>
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Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
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---
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drivers/i2c/busses/i2c-imx.c | 9 ++++-----
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1 file changed, 4 insertions(+), 5 deletions(-)
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--- a/drivers/i2c/busses/i2c-imx.c
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+++ b/drivers/i2c/busses/i2c-imx.c
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@@ -1066,12 +1066,15 @@ static int i2c_imx_xfer(struct i2c_adapt
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dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
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-
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if (!pm_runtime_enabled(i2c_imx->adapter.dev.parent)) {
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pm_runtime_enable(i2c_imx->adapter.dev.parent);
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enable_runtime_pm = true;
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}
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+ result = pm_runtime_get_sync(i2c_imx->adapter.dev.parent);
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+ if (result < 0)
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+ goto out;
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+
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/*
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* workround for ERR010027: ensure that the I2C BUS is idle
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* before switching to master mode and attempting a Start cycle
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@@ -1085,10 +1088,6 @@ static int i2c_imx_xfer(struct i2c_adapt
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goto out;
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}
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- result = pm_runtime_get_sync(i2c_imx->adapter.dev.parent);
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- if (result < 0)
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- goto out;
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-
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/* Start I2C transfer */
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result = i2c_imx_start(i2c_imx);
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if (result) {
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