diff options
Diffstat (limited to 'drivers/spi')
-rw-r--r-- | drivers/spi/spi-bcm63xx.c | 149 |
1 files changed, 89 insertions, 60 deletions
diff --git a/drivers/spi/spi-bcm63xx.c b/drivers/spi/spi-bcm63xx.c index f01b264..63b0028 100644 --- a/drivers/spi/spi-bcm63xx.c +++ b/drivers/spi/spi-bcm63xx.c @@ -1,7 +1,7 @@ /* * Broadcom BCM63xx SPI controller support * - * Copyright (C) 2009-2011 Florian Fainelli <florian@openwrt.org> + * Copyright (C) 2009-2012 Florian Fainelli <florian@openwrt.org> * Copyright (C) 2010 Tanguy Bouzeloc <tanguy.bouzeloc@efixo.com> * * This program is free software; you can redistribute it and/or @@ -30,6 +30,8 @@ #include <linux/spi/spi.h> #include <linux/completion.h> #include <linux/err.h> +#include <linux/workqueue.h> +#include <linux/pm_runtime.h> #include <bcm63xx_dev_spi.h> @@ -96,17 +98,12 @@ static const unsigned bcm63xx_spi_freq_table[SPI_CLK_MASK][2] = { { 391000, SPI_CLK_0_391MHZ } }; -static int bcm63xx_spi_setup_transfer(struct spi_device *spi, - struct spi_transfer *t) +static int bcm63xx_spi_check_transfer(struct spi_device *spi, + struct spi_transfer *t) { - struct bcm63xx_spi *bs = spi_master_get_devdata(spi->master); u8 bits_per_word; - u8 clk_cfg, reg; - u32 hz; - int i; bits_per_word = (t) ? t->bits_per_word : spi->bits_per_word; - hz = (t) ? t->speed_hz : spi->max_speed_hz; if (bits_per_word != 8) { dev_err(&spi->dev, "%s, unsupported bits_per_word=%d\n", __func__, bits_per_word); @@ -119,6 +116,19 @@ static int bcm63xx_spi_setup_transfer(struct spi_device *spi, return -EINVAL; } + return 0; +} + +static void bcm63xx_spi_setup_transfer(struct spi_device *spi, + struct spi_transfer *t) +{ + struct bcm63xx_spi *bs = spi_master_get_devdata(spi->master); + u32 hz; + u8 clk_cfg, reg; + int i; + + hz = (t) ? t->speed_hz : spi->max_speed_hz; + /* Find the closest clock configuration */ for (i = 0; i < SPI_CLK_MASK; i++) { if (hz <= bcm63xx_spi_freq_table[i][0]) { @@ -139,8 +149,6 @@ static int bcm63xx_spi_setup_transfer(struct spi_device *spi, bcm_spi_writeb(bs, reg, SPI_CLK_CFG); dev_dbg(&spi->dev, "Setting clock register to %02x (hz %d)\n", clk_cfg, hz); - - return 0; } /* the spi->mode bits understood by this driver: */ @@ -165,7 +173,7 @@ static int bcm63xx_spi_setup(struct spi_device *spi) return -EINVAL; } - ret = bcm63xx_spi_setup_transfer(spi, NULL); + ret = bcm63xx_spi_check_transfer(spi, NULL); if (ret < 0) { dev_err(&spi->dev, "setup: unsupported mode bits %x\n", spi->mode & ~MODEBITS); @@ -190,28 +198,29 @@ static void bcm63xx_spi_fill_tx_fifo(struct bcm63xx_spi *bs) bs->remaining_bytes -= size; } -static int bcm63xx_txrx_bufs(struct spi_device *spi, struct spi_transfer *t) +static unsigned int bcm63xx_txrx_bufs(struct spi_device *spi, + struct spi_transfer *t) { struct bcm63xx_spi *bs = spi_master_get_devdata(spi->master); u16 msg_ctl; u16 cmd; + /* Disable the CMD_DONE interrupt */ + bcm_spi_writeb(bs, 0, SPI_INT_MASK); + dev_dbg(&spi->dev, "txrx: tx %p, rx %p, len %d\n", t->tx_buf, t->rx_buf, t->len); /* Transmitter is inhibited */ bs->tx_ptr = t->tx_buf; bs->rx_ptr = t->rx_buf; - init_completion(&bs->done); if (t->tx_buf) { bs->remaining_bytes = t->len; bcm63xx_spi_fill_tx_fifo(bs); } - /* Enable the command done interrupt which - * we use to determine completion of a command */ - bcm_spi_writeb(bs, SPI_INTR_CMD_DONE, SPI_INT_MASK); + init_completion(&bs->done); /* Fill in the Message control register */ msg_ctl = (t->len << SPI_BYTE_CNT_SHIFT); @@ -230,33 +239,76 @@ static int bcm63xx_txrx_bufs(struct spi_device *spi, struct spi_transfer *t) cmd |= (0 << SPI_CMD_PREPEND_BYTE_CNT_SHIFT); cmd |= (spi->chip_select << SPI_CMD_DEVICE_ID_SHIFT); bcm_spi_writew(bs, cmd, SPI_CMD); - wait_for_completion(&bs->done); - /* Disable the CMD_DONE interrupt */ - bcm_spi_writeb(bs, 0, SPI_INT_MASK); + /* Enable the CMD_DONE interrupt */ + bcm_spi_writeb(bs, SPI_INTR_CMD_DONE, SPI_INT_MASK); return t->len - bs->remaining_bytes; } -static int bcm63xx_transfer(struct spi_device *spi, struct spi_message *m) +static int bcm63xx_spi_prepare_transfer(struct spi_master *master) { - struct bcm63xx_spi *bs = spi_master_get_devdata(spi->master); - struct spi_transfer *t; - int ret = 0; + struct bcm63xx_spi *bs = spi_master_get_devdata(master); - if (unlikely(list_empty(&m->transfers))) - return -EINVAL; + pm_runtime_get_sync(&bs->pdev->dev); - if (bs->stopping) - return -ESHUTDOWN; + return 0; +} + +static int bcm63xx_spi_unprepare_transfer(struct spi_master *master) +{ + struct bcm63xx_spi *bs = spi_master_get_devdata(master); + + pm_runtime_put(&bs->pdev->dev); + + return 0; +} + +static int bcm63xx_spi_transfer_one(struct spi_master *master, + struct spi_message *m) +{ + struct bcm63xx_spi *bs = spi_master_get_devdata(master); + struct spi_transfer *t; + struct spi_device *spi = m->spi; + int status = 0; + unsigned int timeout = 0; list_for_each_entry(t, &m->transfers, transfer_list) { - ret += bcm63xx_txrx_bufs(spi, t); - } + unsigned int len = t->len; + u8 rx_tail; - m->complete(m->context); + status = bcm63xx_spi_check_transfer(spi, t); + if (status < 0) + goto exit; - return ret; + /* configure adapter for a new transfer */ + bcm63xx_spi_setup_transfer(spi, t); + + while (len) { + /* send the data */ + len -= bcm63xx_txrx_bufs(spi, t); + + timeout = wait_for_completion_timeout(&bs->done, HZ); + if (!timeout) { + status = -ETIMEDOUT; + goto exit; + } + + /* read out all data */ + rx_tail = bcm_spi_readb(bs, SPI_RX_TAIL); + + /* Read out all the data */ + if (rx_tail) + memcpy_fromio(bs->rx_ptr, bs->rx_io, rx_tail); + } + + m->actual_length += t->len; + } +exit: + m->status = status; + spi_finalize_current_message(master); + + return 0; } /* This driver supports single master mode only. Hence @@ -267,39 +319,15 @@ static irqreturn_t bcm63xx_spi_interrupt(int irq, void *dev_id) struct spi_master *master = (struct spi_master *)dev_id; struct bcm63xx_spi *bs = spi_master_get_devdata(master); u8 intr; - u16 cmd; /* Read interupts and clear them immediately */ intr = bcm_spi_readb(bs, SPI_INT_STATUS); bcm_spi_writeb(bs, SPI_INTR_CLEAR_ALL, SPI_INT_STATUS); bcm_spi_writeb(bs, 0, SPI_INT_MASK); - /* A tansfer completed */ - if (intr & SPI_INTR_CMD_DONE) { - u8 rx_tail; - - rx_tail = bcm_spi_readb(bs, SPI_RX_TAIL); - - /* Read out all the data */ - if (rx_tail) - memcpy_fromio(bs->rx_ptr, bs->rx_io, rx_tail); - - /* See if there is more data to send */ - if (bs->remaining_bytes > 0) { - bcm63xx_spi_fill_tx_fifo(bs); - - /* Start the transfer */ - bcm_spi_writew(bs, SPI_HD_W << SPI_MSG_TYPE_SHIFT, - SPI_MSG_CTL); - cmd = bcm_spi_readw(bs, SPI_CMD); - cmd |= SPI_CMD_START_IMMEDIATE; - cmd |= (0 << SPI_CMD_PREPEND_BYTE_CNT_SHIFT); - bcm_spi_writeb(bs, SPI_INTR_CMD_DONE, SPI_INT_MASK); - bcm_spi_writew(bs, cmd, SPI_CMD); - } else { - complete(&bs->done); - } - } + /* A transfer completed */ + if (intr & SPI_INTR_CMD_DONE) + complete(&bs->done); return IRQ_HANDLED; } @@ -345,7 +373,6 @@ static int __devinit bcm63xx_spi_probe(struct platform_device *pdev) } bs = spi_master_get_devdata(master); - init_completion(&bs->done); platform_set_drvdata(pdev, master); bs->pdev = pdev; @@ -379,7 +406,9 @@ static int __devinit bcm63xx_spi_probe(struct platform_device *pdev) master->bus_num = pdata->bus_num; master->num_chipselect = pdata->num_chipselect; master->setup = bcm63xx_spi_setup; - master->transfer = bcm63xx_transfer; + master->prepare_transfer_hardware = bcm63xx_spi_prepare_transfer; + master->unprepare_transfer_hardware = bcm63xx_spi_unprepare_transfer; + master->transfer_one_message = bcm63xx_spi_transfer_one; bs->speed_hz = pdata->speed_hz; bs->stopping = 0; bs->tx_io = (u8 *)(bs->regs + bcm63xx_spireg(SPI_MSG_DATA)); |