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path: root/drivers/spi/dw_spi.c
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Diffstat (limited to 'drivers/spi/dw_spi.c')
-rw-r--r--drivers/spi/dw_spi.c57
1 files changed, 37 insertions, 20 deletions
diff --git a/drivers/spi/dw_spi.c b/drivers/spi/dw_spi.c
index 90439314cf67..22af77f98816 100644
--- a/drivers/spi/dw_spi.c
+++ b/drivers/spi/dw_spi.c
@@ -164,20 +164,23 @@ static inline void mrst_spi_debugfs_remove(struct dw_spi *dws)
static void wait_till_not_busy(struct dw_spi *dws)
{
- unsigned long end = jiffies + 1 + usecs_to_jiffies(1000);
+ unsigned long end = jiffies + 1 + usecs_to_jiffies(5000);
while (time_before(jiffies, end)) {
if (!(dw_readw(dws, sr) & SR_BUSY))
return;
+ cpu_relax();
}
dev_err(&dws->master->dev,
- "DW SPI: Status keeps busy for 1000us after a read/write!\n");
+ "DW SPI: Status keeps busy for 5000us after a read/write!\n");
}
static void flush(struct dw_spi *dws)
{
- while (dw_readw(dws, sr) & SR_RF_NOT_EMPT)
+ while (dw_readw(dws, sr) & SR_RF_NOT_EMPT) {
dw_readw(dws, dr);
+ cpu_relax();
+ }
wait_till_not_busy(dws);
}
@@ -285,8 +288,10 @@ static void *next_transfer(struct dw_spi *dws)
*/
static int map_dma_buffers(struct dw_spi *dws)
{
- if (!dws->cur_msg->is_dma_mapped || !dws->dma_inited
- || !dws->cur_chip->enable_dma)
+ if (!dws->cur_msg->is_dma_mapped
+ || !dws->dma_inited
+ || !dws->cur_chip->enable_dma
+ || !dws->dma_ops)
return 0;
if (dws->cur_transfer->tx_dma)
@@ -338,7 +343,7 @@ static void int_error_stop(struct dw_spi *dws, const char *msg)
tasklet_schedule(&dws->pump_transfers);
}
-static void transfer_complete(struct dw_spi *dws)
+void dw_spi_xfer_done(struct dw_spi *dws)
{
/* Update total byte transfered return count actual bytes read */
dws->cur_msg->actual_length += dws->len;
@@ -353,6 +358,7 @@ static void transfer_complete(struct dw_spi *dws)
} else
tasklet_schedule(&dws->pump_transfers);
}
+EXPORT_SYMBOL_GPL(dw_spi_xfer_done);
static irqreturn_t interrupt_transfer(struct dw_spi *dws)
{
@@ -384,7 +390,7 @@ static irqreturn_t interrupt_transfer(struct dw_spi *dws)
if (dws->tx_end > dws->tx)
spi_umask_intr(dws, SPI_INT_TXEI);
else
- transfer_complete(dws);
+ dw_spi_xfer_done(dws);
}
return IRQ_HANDLED;
@@ -413,12 +419,13 @@ static void poll_transfer(struct dw_spi *dws)
{
while (dws->write(dws))
dws->read(dws);
+ /*
+ * There is a possibility that the last word of a transaction
+ * will be lost if data is not ready. Re-read to solve this issue.
+ */
+ dws->read(dws);
- transfer_complete(dws);
-}
-
-static void dma_transfer(struct dw_spi *dws, int cs_change)
-{
+ dw_spi_xfer_done(dws);
}
static void pump_transfers(unsigned long data)
@@ -587,7 +594,7 @@ static void pump_transfers(unsigned long data)
spi_set_clk(dws, clk_div ? clk_div : chip->clk_div);
spi_chip_sel(dws, spi->chip_select);
- /* Set the interrupt mask, for poll mode just diable all int */
+ /* Set the interrupt mask, for poll mode just disable all int */
spi_mask_intr(dws, 0xff);
if (imask)
spi_umask_intr(dws, imask);
@@ -600,7 +607,7 @@ static void pump_transfers(unsigned long data)
}
if (dws->dma_mapped)
- dma_transfer(dws, cs_change);
+ dws->dma_ops->dma_transfer(dws, cs_change);
if (chip->poll_mode)
poll_transfer(dws);
@@ -896,11 +903,17 @@ int __devinit dw_spi_add_host(struct dw_spi *dws)
master->setup = dw_spi_setup;
master->transfer = dw_spi_transfer;
- dws->dma_inited = 0;
-
/* Basic HW init */
spi_hw_init(dws);
+ if (dws->dma_ops && dws->dma_ops->dma_init) {
+ ret = dws->dma_ops->dma_init(dws);
+ if (ret) {
+ dev_warn(&master->dev, "DMA init failed\n");
+ dws->dma_inited = 0;
+ }
+ }
+
/* Initial and start queue */
ret = init_queue(dws);
if (ret) {
@@ -925,6 +938,8 @@ int __devinit dw_spi_add_host(struct dw_spi *dws)
err_queue_alloc:
destroy_queue(dws);
+ if (dws->dma_ops && dws->dma_ops->dma_exit)
+ dws->dma_ops->dma_exit(dws);
err_diable_hw:
spi_enable_chip(dws, 0);
free_irq(dws->irq, dws);
@@ -933,7 +948,7 @@ err_free_master:
exit:
return ret;
}
-EXPORT_SYMBOL(dw_spi_add_host);
+EXPORT_SYMBOL_GPL(dw_spi_add_host);
void __devexit dw_spi_remove_host(struct dw_spi *dws)
{
@@ -949,6 +964,8 @@ void __devexit dw_spi_remove_host(struct dw_spi *dws)
dev_err(&dws->master->dev, "dw_spi_remove: workqueue will not "
"complete, message memory not freed\n");
+ if (dws->dma_ops && dws->dma_ops->dma_exit)
+ dws->dma_ops->dma_exit(dws);
spi_enable_chip(dws, 0);
/* Disable clk */
spi_set_clk(dws, 0);
@@ -957,7 +974,7 @@ void __devexit dw_spi_remove_host(struct dw_spi *dws)
/* Disconnect from the SPI framework */
spi_unregister_master(dws->master);
}
-EXPORT_SYMBOL(dw_spi_remove_host);
+EXPORT_SYMBOL_GPL(dw_spi_remove_host);
int dw_spi_suspend_host(struct dw_spi *dws)
{
@@ -970,7 +987,7 @@ int dw_spi_suspend_host(struct dw_spi *dws)
spi_set_clk(dws, 0);
return ret;
}
-EXPORT_SYMBOL(dw_spi_suspend_host);
+EXPORT_SYMBOL_GPL(dw_spi_suspend_host);
int dw_spi_resume_host(struct dw_spi *dws)
{
@@ -982,7 +999,7 @@ int dw_spi_resume_host(struct dw_spi *dws)
dev_err(&dws->master->dev, "fail to start queue (%d)\n", ret);
return ret;
}
-EXPORT_SYMBOL(dw_spi_resume_host);
+EXPORT_SYMBOL_GPL(dw_spi_resume_host);
MODULE_AUTHOR("Feng Tang <feng.tang@intel.com>");
MODULE_DESCRIPTION("Driver for DesignWare SPI controller core");