diff options
author | Mauro Carvalho Chehab <mchehab@infradead.org> | 2008-07-27 12:25:57 -0300 |
---|---|---|
committer | Mauro Carvalho Chehab <mchehab@infradead.org> | 2008-07-27 12:25:57 -0300 |
commit | 50cb993ea6cd187bfed085cb3e0747066edeb02f (patch) | |
tree | 61edac62c6c5bc07c59e4369c50c6821ad77f2c0 /drivers/spi/au1550_spi.c | |
parent | 445c2714cf72817ab1ad3ca894c6d9b2047b3a3e (diff) | |
parent | 8be1a6d6c77ab4532e4476fdb8177030ef48b52c (diff) |
Merge ../linux-2.6
Diffstat (limited to 'drivers/spi/au1550_spi.c')
-rw-r--r-- | drivers/spi/au1550_spi.c | 213 |
1 files changed, 126 insertions, 87 deletions
diff --git a/drivers/spi/au1550_spi.c b/drivers/spi/au1550_spi.c index 072c4a59533..87b73e0169c 100644 --- a/drivers/spi/au1550_spi.c +++ b/drivers/spi/au1550_spi.c @@ -26,6 +26,7 @@ #include <linux/errno.h> #include <linux/device.h> #include <linux/platform_device.h> +#include <linux/resource.h> #include <linux/spi/spi.h> #include <linux/spi/spi_bitbang.h> #include <linux/dma-mapping.h> @@ -81,6 +82,7 @@ struct au1550_spi { struct spi_master *master; struct device *dev; struct au1550_spi_info *pdata; + struct resource *ioarea; }; @@ -96,6 +98,8 @@ static dbdev_tab_t au1550_spi_mem_dbdev = .dev_intpolarity = 0 }; +static int ddma_memid; /* id to above mem dma device */ + static void au1550_spi_bits_handlers_set(struct au1550_spi *hw, int bpw); @@ -330,7 +334,7 @@ static int au1550_spi_dma_rxtmp_alloc(struct au1550_spi *hw, unsigned size) hw->dma_rx_tmpbuf_size = size; hw->dma_rx_tmpbuf_addr = dma_map_single(hw->dev, hw->dma_rx_tmpbuf, size, DMA_FROM_DEVICE); - if (dma_mapping_error(hw->dma_rx_tmpbuf_addr)) { + if (dma_mapping_error(hw->dev, hw->dma_rx_tmpbuf_addr)) { kfree(hw->dma_rx_tmpbuf); hw->dma_rx_tmpbuf = 0; hw->dma_rx_tmpbuf_size = 0; @@ -374,7 +378,7 @@ static int au1550_spi_dma_txrxb(struct spi_device *spi, struct spi_transfer *t) dma_rx_addr = dma_map_single(hw->dev, (void *)t->rx_buf, t->len, DMA_FROM_DEVICE); - if (dma_mapping_error(dma_rx_addr)) + if (dma_mapping_error(hw->dev, dma_rx_addr)) dev_err(hw->dev, "rx dma map error\n"); } } else { @@ -397,7 +401,7 @@ static int au1550_spi_dma_txrxb(struct spi_device *spi, struct spi_transfer *t) dma_tx_addr = dma_map_single(hw->dev, (void *)t->tx_buf, t->len, DMA_TO_DEVICE); - if (dma_mapping_error(dma_tx_addr)) + if (dma_mapping_error(hw->dev, dma_tx_addr)) dev_err(hw->dev, "tx dma map error\n"); } } else { @@ -480,9 +484,13 @@ static irqreturn_t au1550_spi_dma_irq_callback(struct au1550_spi *hw) au1xxx_dbdma_reset(hw->dma_tx_ch); au1550_spi_reset_fifos(hw); - dev_err(hw->dev, - "Unexpected SPI error: event=0x%x stat=0x%x!\n", - evnt, stat); + if (evnt == PSC_SPIEVNT_RO) + dev_err(hw->dev, + "dma transfer: receive FIFO overflow!\n"); + else + dev_err(hw->dev, + "dma transfer: unexpected SPI error " + "(event=0x%x stat=0x%x)!\n", evnt, stat); complete(&hw->master_done); return IRQ_HANDLED; @@ -592,17 +600,17 @@ static irqreturn_t au1550_spi_pio_irq_callback(struct au1550_spi *hw) if ((evnt & (PSC_SPIEVNT_MM | PSC_SPIEVNT_RO | PSC_SPIEVNT_RU | PSC_SPIEVNT_TO - | PSC_SPIEVNT_TU | PSC_SPIEVNT_SD)) + | PSC_SPIEVNT_SD)) != 0) { - dev_err(hw->dev, - "Unexpected SPI error: event=0x%x stat=0x%x!\n", - evnt, stat); /* * due to an error we consider transfer as done, * so mask all events until before next transfer start */ au1550_spi_mask_ack_all(hw); au1550_spi_reset_fifos(hw); + dev_err(hw->dev, + "pio transfer: unexpected SPI error " + "(event=0x%x stat=0x%x)!\n", evnt, stat); complete(&hw->master_done); return IRQ_HANDLED; } @@ -616,27 +624,50 @@ static irqreturn_t au1550_spi_pio_irq_callback(struct au1550_spi *hw) stat = hw->regs->psc_spistat; au_sync(); - if ((stat & PSC_SPISTAT_RE) == 0 && hw->rx_count < hw->len) { + /* + * Take care to not let the Rx FIFO overflow. + * + * We only write a byte if we have read one at least. Initially, + * the write fifo is full, so we should read from the read fifo + * first. + * In case we miss a word from the read fifo, we should get a + * RO event and should back out. + */ + if (!(stat & PSC_SPISTAT_RE) && hw->rx_count < hw->len) { hw->rx_word(hw); - /* ack the receive request event */ - hw->regs->psc_spievent = PSC_SPIEVNT_RR; - au_sync(); busy = 1; - } - if ((stat & PSC_SPISTAT_TF) == 0 && hw->tx_count < hw->len) { - hw->tx_word(hw); - /* ack the transmit request event */ - hw->regs->psc_spievent = PSC_SPIEVNT_TR; - au_sync(); - busy = 1; + if (!(stat & PSC_SPISTAT_TF) && hw->tx_count < hw->len) + hw->tx_word(hw); } } while (busy); - evnt = hw->regs->psc_spievent; + hw->regs->psc_spievent = PSC_SPIEVNT_RR | PSC_SPIEVNT_TR; au_sync(); - if (hw->rx_count >= hw->len || (evnt & PSC_SPIEVNT_MD) != 0) { + /* + * Restart the SPI transmission in case of a transmit underflow. + * This seems to work despite the notes in the Au1550 data book + * of Figure 8-4 with flowchart for SPI master operation: + * + * """Note 1: An XFR Error Interrupt occurs, unless masked, + * for any of the following events: Tx FIFO Underflow, + * Rx FIFO Overflow, or Multiple-master Error + * Note 2: In case of a Tx Underflow Error, all zeroes are + * transmitted.""" + * + * By simply restarting the spi transfer on Tx Underflow Error, + * we assume that spi transfer was paused instead of zeroes + * transmittion mentioned in the Note 2 of Au1550 data book. + */ + if (evnt & PSC_SPIEVNT_TU) { + hw->regs->psc_spievent = PSC_SPIEVNT_TU | PSC_SPIEVNT_MD; + au_sync(); + hw->regs->psc_spipcr = PSC_SPIPCR_MS; + au_sync(); + } + + if (hw->rx_count >= hw->len) { /* transfer completed successfully */ au1550_spi_mask_ack_all(hw); complete(&hw->master_done); @@ -725,6 +756,8 @@ static void __init au1550_spi_setup_psc_as_spi(struct au1550_spi *hw) stat = hw->regs->psc_spistat; au_sync(); } while ((stat & PSC_SPISTAT_DR) == 0); + + au1550_spi_reset_fifos(hw); } @@ -732,6 +765,7 @@ static int __init au1550_spi_probe(struct platform_device *pdev) { struct au1550_spi *hw; struct spi_master *master; + struct resource *r; int err = 0; master = spi_alloc_master(&pdev->dev, sizeof(struct au1550_spi)); @@ -753,76 +787,64 @@ static int __init au1550_spi_probe(struct platform_device *pdev) goto err_no_pdata; } - platform_set_drvdata(pdev, hw); - - init_completion(&hw->master_done); - - hw->bitbang.master = hw->master; - hw->bitbang.setup_transfer = au1550_spi_setupxfer; - hw->bitbang.chipselect = au1550_spi_chipsel; - hw->bitbang.master->setup = au1550_spi_setup; - hw->bitbang.txrx_bufs = au1550_spi_txrx_bufs; + r = platform_get_resource(pdev, IORESOURCE_IRQ, 0); + if (!r) { + dev_err(&pdev->dev, "no IRQ\n"); + err = -ENODEV; + goto err_no_iores; + } + hw->irq = r->start; + + hw->usedma = 0; + r = platform_get_resource(pdev, IORESOURCE_DMA, 0); + if (r) { + hw->dma_tx_id = r->start; + r = platform_get_resource(pdev, IORESOURCE_DMA, 1); + if (r) { + hw->dma_rx_id = r->start; + if (usedma && ddma_memid) { + if (pdev->dev.dma_mask == NULL) + dev_warn(&pdev->dev, "no dma mask\n"); + else + hw->usedma = 1; + } + } + } - switch (hw->pdata->bus_num) { - case 0: - hw->irq = AU1550_PSC0_INT; - hw->regs = (volatile psc_spi_t *)PSC0_BASE_ADDR; - hw->dma_rx_id = DSCR_CMD0_PSC0_RX; - hw->dma_tx_id = DSCR_CMD0_PSC0_TX; - break; - case 1: - hw->irq = AU1550_PSC1_INT; - hw->regs = (volatile psc_spi_t *)PSC1_BASE_ADDR; - hw->dma_rx_id = DSCR_CMD0_PSC1_RX; - hw->dma_tx_id = DSCR_CMD0_PSC1_TX; - break; - case 2: - hw->irq = AU1550_PSC2_INT; - hw->regs = (volatile psc_spi_t *)PSC2_BASE_ADDR; - hw->dma_rx_id = DSCR_CMD0_PSC2_RX; - hw->dma_tx_id = DSCR_CMD0_PSC2_TX; - break; - case 3: - hw->irq = AU1550_PSC3_INT; - hw->regs = (volatile psc_spi_t *)PSC3_BASE_ADDR; - hw->dma_rx_id = DSCR_CMD0_PSC3_RX; - hw->dma_tx_id = DSCR_CMD0_PSC3_TX; - break; - default: - dev_err(&pdev->dev, "Wrong bus_num of SPI\n"); - err = -ENOENT; - goto err_no_pdata; + r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!r) { + dev_err(&pdev->dev, "no mmio resource\n"); + err = -ENODEV; + goto err_no_iores; } - if (request_mem_region((unsigned long)hw->regs, sizeof(psc_spi_t), - pdev->name) == NULL) { + hw->ioarea = request_mem_region(r->start, sizeof(psc_spi_t), + pdev->name); + if (!hw->ioarea) { dev_err(&pdev->dev, "Cannot reserve iomem region\n"); err = -ENXIO; goto err_no_iores; } - - if (usedma) { - if (pdev->dev.dma_mask == NULL) - dev_warn(&pdev->dev, "no dma mask\n"); - else - hw->usedma = 1; + hw->regs = (psc_spi_t __iomem *)ioremap(r->start, sizeof(psc_spi_t)); + if (!hw->regs) { + dev_err(&pdev->dev, "cannot ioremap\n"); + err = -ENXIO; + goto err_ioremap; } - if (hw->usedma) { - /* - * create memory device with 8 bits dev_devwidth - * needed for proper byte ordering to spi fifo - */ - int memid = au1xxx_ddma_add_device(&au1550_spi_mem_dbdev); - if (!memid) { - dev_err(&pdev->dev, - "Cannot create dma 8 bit mem device\n"); - err = -ENXIO; - goto err_dma_add_dev; - } + platform_set_drvdata(pdev, hw); + + init_completion(&hw->master_done); + + hw->bitbang.master = hw->master; + hw->bitbang.setup_transfer = au1550_spi_setupxfer; + hw->bitbang.chipselect = au1550_spi_chipsel; + hw->bitbang.master->setup = au1550_spi_setup; + hw->bitbang.txrx_bufs = au1550_spi_txrx_bufs; - hw->dma_tx_ch = au1xxx_dbdma_chan_alloc(memid, + if (hw->usedma) { + hw->dma_tx_ch = au1xxx_dbdma_chan_alloc(ddma_memid, hw->dma_tx_id, NULL, (void *)hw); if (hw->dma_tx_ch == 0) { dev_err(&pdev->dev, @@ -841,7 +863,7 @@ static int __init au1550_spi_probe(struct platform_device *pdev) hw->dma_rx_ch = au1xxx_dbdma_chan_alloc(hw->dma_rx_id, - memid, NULL, (void *)hw); + ddma_memid, NULL, (void *)hw); if (hw->dma_rx_ch == 0) { dev_err(&pdev->dev, "Cannot allocate rx dma channel\n"); @@ -874,7 +896,7 @@ static int __init au1550_spi_probe(struct platform_device *pdev) goto err_no_irq; } - master->bus_num = hw->pdata->bus_num; + master->bus_num = pdev->id; master->num_chipselect = hw->pdata->num_chipselect; /* @@ -924,8 +946,11 @@ err_no_txdma_descr: au1xxx_dbdma_chan_free(hw->dma_tx_ch); err_no_txdma: -err_dma_add_dev: - release_mem_region((unsigned long)hw->regs, sizeof(psc_spi_t)); + iounmap((void __iomem *)hw->regs); + +err_ioremap: + release_resource(hw->ioarea); + kfree(hw->ioarea); err_no_iores: err_no_pdata: @@ -944,7 +969,9 @@ static int __exit au1550_spi_remove(struct platform_device *pdev) spi_bitbang_stop(&hw->bitbang); free_irq(hw->irq, hw); - release_mem_region((unsigned long)hw->regs, sizeof(psc_spi_t)); + iounmap((void __iomem *)hw->regs); + release_resource(hw->ioarea); + kfree(hw->ioarea); if (hw->usedma) { au1550_spi_dma_rxtmp_free(hw); @@ -971,12 +998,24 @@ static struct platform_driver au1550_spi_drv = { static int __init au1550_spi_init(void) { + /* + * create memory device with 8 bits dev_devwidth + * needed for proper byte ordering to spi fifo + */ + if (usedma) { + ddma_memid = au1xxx_ddma_add_device(&au1550_spi_mem_dbdev); + if (!ddma_memid) + printk(KERN_ERR "au1550-spi: cannot add memory" + "dbdma device\n"); + } return platform_driver_probe(&au1550_spi_drv, au1550_spi_probe); } module_init(au1550_spi_init); static void __exit au1550_spi_exit(void) { + if (usedma && ddma_memid) + au1xxx_ddma_del_device(ddma_memid); platform_driver_unregister(&au1550_spi_drv); } module_exit(au1550_spi_exit); |