From 5b00f40f90e7b17c11cf388680f43e8466b3666d Mon Sep 17 00:00:00 2001 From: San Mehat Date: Sat, 21 Nov 2009 09:22:14 -0800 Subject: msm: Add 'execute' datamover callback Based on a patch from Brent DeGraaf: "The datamover supports channels which can be shared amongst devices. As a result, the actual data transfer may occur some time after the request is queued up. Some devices such as mmc host controllers will timeout if a command is issued too far in advance of the actual transfer, so if dma to other devices on the same channel is already in progress or queued up, the added delay can cause pending transfers to fail before they start. This change extends the api to allow a user callback to be invoked just before the actual transfer takes place, thus allowing actions directly associated with the dma transfer, such as device commands, to be invoked with precise timing. Without this mechanism, there is no way for a driver to realize this timing. Also adds a user pointer to the command structure for use by the caller to reference information that may be needed by the callback routine for proper identification and processing associated with that specific request. This change is necessary to fix problems associated with excessive command timeouts and race conditions in the mmc driver." This patch also fixes all the callers of msm_dmov_enqueue_cmd() to ensure their callback function is NULL. Signed-off-by: San Mehat Cc: Brent DeGraaf Cc: Brian Swetland Signed-off-by: Daniel Walker --- arch/arm/mach-msm/dma.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'arch/arm/mach-msm/dma.c') diff --git a/arch/arm/mach-msm/dma.c b/arch/arm/mach-msm/dma.c index f5420f9585c..8df798ac70c 100644 --- a/arch/arm/mach-msm/dma.c +++ b/arch/arm/mach-msm/dma.c @@ -63,6 +63,8 @@ void msm_dmov_enqueue_cmd(unsigned id, struct msm_dmov_cmd *cmd) writel(DMOV_CONFIG_IRQ_EN, DMOV_CONFIG(id)); } #endif + if (cmd->execute_func) + cmd->execute_func(cmd); PRINT_IO("msm_dmov_enqueue_cmd(%d), start command, status %x\n", id, status); list_add_tail(&cmd->list, &active_commands[id]); if (!channel_active) @@ -108,6 +110,7 @@ int msm_dmov_exec_cmd(unsigned id, unsigned int cmdptr) cmd.dmov_cmd.cmdptr = cmdptr; cmd.dmov_cmd.complete_func = dmov_exec_cmdptr_complete_func; + cmd.dmov_cmd.execute_func = NULL; cmd.id = id; init_completion(&cmd.complete); @@ -210,6 +213,8 @@ static irqreturn_t msm_datamover_irq_handler(int irq, void *dev_id) cmd = list_entry(ready_commands[id].next, typeof(*cmd), list); list_del(&cmd->list); list_add_tail(&cmd->list, &active_commands[id]); + if (cmd->execute_func) + cmd->execute_func(cmd); PRINT_FLOW("msm_datamover_irq_handler id %d, start command\n", id); writel(cmd->cmdptr, DMOV_CMD_PTR(id)); } -- cgit v1.2.3-70-g09d2 From 6d7b7d578f2c182f77ab6dd1c375f848f38ea1a6 Mon Sep 17 00:00:00 2001 From: Daniel Walker Date: Thu, 20 May 2010 15:39:33 -0700 Subject: msm: dma: add completion.h header At some point this was exposed (not sure how), linux-2.6/arch/arm/mach-msm/dma.c:92: error: field 'complete' has incomplete type linux-2.6/arch/arm/mach-msm/dma.c: In function 'dmov_exec_cmdptr_complete_func': linux-2.6/arch/arm/mach-msm/dma.c:108: error: implicit declaration of function 'complete' linux-2.6/arch/arm/mach-msm/dma.c: In function 'msm_dmov_exec_cmd': linux-2.6/arch/arm/mach-msm/dma.c:120: error: implicit declaration of function 'init_completion' linux-2.6/arch/arm/mach-msm/dma.c:123: error: implicit declaration of function 'wait_for_completion' and the fix is just to add the header. Signed-off-by: Daniel Walker --- arch/arm/mach-msm/dma.c | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/arm/mach-msm/dma.c') diff --git a/arch/arm/mach-msm/dma.c b/arch/arm/mach-msm/dma.c index d029d1f5f9e..02cae5e2951 100644 --- a/arch/arm/mach-msm/dma.c +++ b/arch/arm/mach-msm/dma.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #define MSM_DMOV_CHANNEL_COUNT 16 -- cgit v1.2.3-70-g09d2