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author | Luka Perkov <luka@openwrt.org> | 2015-12-28 04:56:13 +0000 |
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committer | Luka Perkov <luka@openwrt.org> | 2015-12-28 04:56:13 +0000 |
commit | 2578f0183c64b49218d2e5714480078adfc6e120 (patch) | |
tree | a5a625b69516c19571414c7cbf2386dfae309787 /target/linux/imx6 | |
parent | 158b5b4231e6e579d76b6fea0eef6bcd87ff4e1b (diff) | |
download | mtk-20170518-2578f0183c64b49218d2e5714480078adfc6e120.zip mtk-20170518-2578f0183c64b49218d2e5714480078adfc6e120.tar.gz mtk-20170518-2578f0183c64b49218d2e5714480078adfc6e120.tar.bz2 |
imx6: add i2c retries for Ventana /dev/i2c-0
On Ventana boards the Gateworks System Controller is the only device on I2C1
(/dev/i2c-0) and it can NAK transfers if it is busy in an ADC loop. Because
this is a multi-function device with several slave addresses it is best to
add retries at the controller level instead of within each slave driver. This
adds a patch that adds 3 retries for i2c transactions only for Ventana boards
and only for I2C1
Signed-off-by: Tim Harvey <tharvey@gateworks.com>
Signed-off-by: Pushpal Sidhu <psidhu@gateworks.com>
SVN-Revision: 48012
Diffstat (limited to 'target/linux/imx6')
-rw-r--r-- | target/linux/imx6/patches-4.3/207-i2c-imx-add-retries-for-NAK-s-on-ventana-boards.patch | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/target/linux/imx6/patches-4.3/207-i2c-imx-add-retries-for-NAK-s-on-ventana-boards.patch b/target/linux/imx6/patches-4.3/207-i2c-imx-add-retries-for-NAK-s-on-ventana-boards.patch new file mode 100644 index 0000000..bfb5707 --- /dev/null +++ b/target/linux/imx6/patches-4.3/207-i2c-imx-add-retries-for-NAK-s-on-ventana-boards.patch @@ -0,0 +1,24 @@ +Index: linux-4.3/drivers/i2c/busses/i2c-imx.c +=================================================================== +--- linux-4.3.orig/drivers/i2c/busses/i2c-imx.c 2015-11-01 16:05:25.000000000 -0800 ++++ linux-4.3/drivers/i2c/busses/i2c-imx.c 2015-12-18 10:39:44.971158318 -0800 +@@ -461,6 +461,8 @@ + { + if (imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR) & I2SR_RXAK) { + dev_dbg(&i2c_imx->adapter.dev, "<%s> No ACK\n", __func__); ++ if (i2c_imx->adapter.retries) ++ return -EAGAIN; + return -EIO; /* No ACK */ + } + +@@ -1010,6 +1012,10 @@ + i2c_imx->adapter.nr = pdev->id; + i2c_imx->adapter.dev.of_node = pdev->dev.of_node; + i2c_imx->base = base; ++ if (of_machine_is_compatible("gw,ventana") && phy_addr == 0x021a0000) { ++ dev_info(&pdev->dev, "Adding retries for Ventana GSC\n"); ++ i2c_imx->adapter.retries = 3; ++ } + + /* Get I2C clock */ + i2c_imx->clk = devm_clk_get(&pdev->dev, NULL); |