This is a note to let you know that I've just added the patch titled i2c: mv64xxx: refactor message start to ensure proper initialization to the 3.12-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: i2c-mv64xxx-refactor-message-start-to-ensure-proper-initialization.patch and it can be found in the queue-3.12 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 79970db213344b4a4034645db5ebfc31571f3fa3 Mon Sep 17 00:00:00 2001 From: Wolfram Sang <wsa@xxxxxxxxxxxxx> Date: Thu, 13 Feb 2014 21:36:29 +0100 Subject: i2c: mv64xxx: refactor message start to ensure proper initialization From: Wolfram Sang <wsa@xxxxxxxxxxxxx> commit 79970db213344b4a4034645db5ebfc31571f3fa3 upstream. Because the offload mechanism can fall back to a standard transfer, having two seperate initialization states is unfortunate. Let's just have one state which does things consistently. This fixes a bug where some preparation was missing when the fallback happened. And it makes the code much easier to follow. To implement this, we put the check if offload is possible at the top of the offload setup function. Signed-off-by: Wolfram Sang <wsa@xxxxxxxxxxxxx> Tested-by: Gregory CLEMENT <gregory.clement@xxxxxxxxxxxxxxxxxx> Fixes: 930ab3d403ae (i2c: mv64xxx: Add I2C Transaction Generator support) Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/i2c/busses/i2c-mv64xxx.c | 33 ++++++++++++++------------------- 1 file changed, 14 insertions(+), 19 deletions(-) --- a/drivers/i2c/busses/i2c-mv64xxx.c +++ b/drivers/i2c/busses/i2c-mv64xxx.c @@ -97,7 +97,6 @@ enum { enum { MV64XXX_I2C_ACTION_INVALID, MV64XXX_I2C_ACTION_CONTINUE, - MV64XXX_I2C_ACTION_OFFLOAD_SEND_START, MV64XXX_I2C_ACTION_SEND_START, MV64XXX_I2C_ACTION_SEND_RESTART, MV64XXX_I2C_ACTION_OFFLOAD_RESTART, @@ -204,6 +203,9 @@ static int mv64xxx_i2c_offload_msg(struc unsigned long ctrl_reg; struct i2c_msg *msg = drv_data->msgs; + if (!drv_data->offload_enabled) + return -EOPNOTSUPP; + drv_data->msg = msg; drv_data->byte_posn = 0; drv_data->bytes_left = msg->len; @@ -433,8 +435,7 @@ mv64xxx_i2c_do_action(struct mv64xxx_i2c drv_data->msgs++; drv_data->num_msgs--; - if (!(drv_data->offload_enabled && - mv64xxx_i2c_offload_msg(drv_data))) { + if (mv64xxx_i2c_offload_msg(drv_data) < 0) { drv_data->cntl_bits |= MV64XXX_I2C_REG_CONTROL_START; writel(drv_data->cntl_bits, drv_data->reg_base + drv_data->reg_offsets.control); @@ -458,15 +459,14 @@ mv64xxx_i2c_do_action(struct mv64xxx_i2c drv_data->reg_base + drv_data->reg_offsets.control); break; - case MV64XXX_I2C_ACTION_OFFLOAD_SEND_START: - if (!mv64xxx_i2c_offload_msg(drv_data)) - break; - else - drv_data->action = MV64XXX_I2C_ACTION_SEND_START; - /* FALLTHRU */ case MV64XXX_I2C_ACTION_SEND_START: - writel(drv_data->cntl_bits | MV64XXX_I2C_REG_CONTROL_START, - drv_data->reg_base + drv_data->reg_offsets.control); + /* Can we offload this msg ? */ + if (mv64xxx_i2c_offload_msg(drv_data) < 0) { + /* No, switch to standard path */ + mv64xxx_i2c_prepare_for_io(drv_data, drv_data->msgs); + writel(drv_data->cntl_bits | MV64XXX_I2C_REG_CONTROL_START, + drv_data->reg_base + drv_data->reg_offsets.control); + } break; case MV64XXX_I2C_ACTION_SEND_ADDR_1: @@ -625,15 +625,10 @@ mv64xxx_i2c_execute_msg(struct mv64xxx_i unsigned long flags; spin_lock_irqsave(&drv_data->lock, flags); - if (drv_data->offload_enabled) { - drv_data->action = MV64XXX_I2C_ACTION_OFFLOAD_SEND_START; - drv_data->state = MV64XXX_I2C_STATE_WAITING_FOR_START_COND; - } else { - mv64xxx_i2c_prepare_for_io(drv_data, msg); - drv_data->action = MV64XXX_I2C_ACTION_SEND_START; - drv_data->state = MV64XXX_I2C_STATE_WAITING_FOR_START_COND; - } + drv_data->action = MV64XXX_I2C_ACTION_SEND_START; + drv_data->state = MV64XXX_I2C_STATE_WAITING_FOR_START_COND; + drv_data->send_stop = is_last; drv_data->block = 1; mv64xxx_i2c_do_action(drv_data); Patches currently in stable-queue which might be from wsa@xxxxxxxxxxxxx are queue-3.12/i2c-mv64xxx-refactor-message-start-to-ensure-proper-initialization.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html