diff options
Diffstat (limited to 'drivers/spi/dw_spi.c')
| -rw-r--r-- | drivers/spi/dw_spi.c | 57 |
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"); |