From mboxrd@z Thu Jan 1 00:00:00 1970 From: gregory.clement@free-electrons.com (Gregory CLEMENT) Date: Fri, 3 Jan 2014 10:59:45 +0100 Subject: [PATCH v2 2/2] i2c: mv64xxx: Fix bus hang on A0 version of the Armada XP SoCs In-Reply-To: <1388743185-24822-1-git-send-email-gregory.clement@free-electrons.com> References: <1388743185-24822-1-git-send-email-gregory.clement@free-electrons.com> Message-ID: <1388743185-24822-3-git-send-email-gregory.clement@free-electrons.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org The first variants of Armada XP SoCs (A0 stepping) have issues related to the i2c controller which prevent to use the offload mechanism and lead to a kernel hang during boot. The driver now check the revision of the SoC. If the revision is not more recent than the A0 or if the driver can't get the SoC revision then it disables the offload mechanism. Cc: stable at vger.kernel.org Signed-off-by: Gregory CLEMENT Acked-by: Wolfram Sang --- drivers/i2c/busses/i2c-mv64xxx.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/drivers/i2c/busses/i2c-mv64xxx.c b/drivers/i2c/busses/i2c-mv64xxx.c index 8be7e42aa4de..634b04d241fb 100644 --- a/drivers/i2c/busses/i2c-mv64xxx.c +++ b/drivers/i2c/busses/i2c-mv64xxx.c @@ -24,6 +24,7 @@ #include #include #include +#include #define MV64XXX_I2C_ADDR_ADDR(val) ((val & 0x7f) << 1) #define MV64XXX_I2C_BAUD_DIV_N(val) (val & 0x7) @@ -779,8 +780,16 @@ mv64xxx_of_config(struct mv64xxx_i2c_data *drv_data, * Transaction Generator support and the errata fix. */ if (of_device_is_compatible(np, "marvell,mv78230-i2c")) { - drv_data->offload_enabled = true; + u32 dev, rev; + drv_data->errata_delay = true; + /* + * Only revison more recent than A0 support offload + * mechanism. In case we can't get the SoC revision + * weplay safe and we don't enable it + */ + if (mvebu_get_soc_id(&rev, &dev) == 0 && dev > MV78XX0_A0_REV) + drv_data->offload_enabled = true; } out: -- 1.8.1.2