Re: [PATCH 1/5] ARM: add PrimeCell generic DMA to PL022 v9
From: Grant Likely
Date: Tue Aug 17 2010 - 00:48:43 EST
On Fri, Aug 06, 2010 at 01:50:19PM +0200, Linus Walleij wrote:
> This extends the PL022 SSP/SPI driver with generic DMA engine
> support using the PrimeCell DMA engine interface. Also fix up the
> test code for the U300 platform.
>
> Acked-by: Grant Likely <grant.likely@xxxxxxxxxxxx>
> Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxxxxxx>
Applied to my next-spi branch. Thanks
g.
> ---
> arch/arm/mach-u300/dummyspichip.c | 1 +
> drivers/spi/amba-pl022.c | 523 ++++++++++++++++++++++++++++++-------
> include/linux/amba/pl022.h | 6 +
> 3 files changed, 442 insertions(+), 88 deletions(-)
>
> diff --git a/arch/arm/mach-u300/dummyspichip.c b/arch/arm/mach-u300/dummyspichip.c
> index 5f55012..5672189 100644
> --- a/arch/arm/mach-u300/dummyspichip.c
> +++ b/arch/arm/mach-u300/dummyspichip.c
> @@ -268,6 +268,7 @@ static struct spi_driver pl022_dummy_driver = {
> .driver = {
> .name = "spi-dummy",
> .owner = THIS_MODULE,
> + .bus = &spi_bus_type,
> },
> .probe = pl022_dummy_probe,
> .remove = __devexit_p(pl022_dummy_remove),
> diff --git a/drivers/spi/amba-pl022.c b/drivers/spi/amba-pl022.c
> index acd35d1..59b3948 100644
> --- a/drivers/spi/amba-pl022.c
> +++ b/drivers/spi/amba-pl022.c
> @@ -27,7 +27,6 @@
> /*
> * TODO:
> * - add timeout on polled transfers
> - * - add generic DMA framework support
> */
>
> #include <linux/init.h>
> @@ -45,6 +44,9 @@
> #include <linux/amba/pl022.h>
> #include <linux/io.h>
> #include <linux/slab.h>
> +#include <linux/dmaengine.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/scatterlist.h>
>
> /*
> * This macro is used to define some register default values.
> @@ -381,6 +383,14 @@ struct pl022 {
> enum ssp_reading read;
> enum ssp_writing write;
> u32 exp_fifo_level;
> + /* DMA settings */
> +#ifdef CONFIG_DMADEVICES
> + struct dma_chan *dma_rx_channel;
> + struct dma_chan *dma_tx_channel;
> + struct sg_table sgt_rx;
> + struct sg_table sgt_tx;
> + char *dummypage;
> +#endif
> };
>
> /**
> @@ -406,7 +416,7 @@ struct chip_data {
> u16 dmacr;
> u16 cpsr;
> u8 n_bytes;
> - u8 enable_dma:1;
> + bool enable_dma;
> enum ssp_reading read;
> enum ssp_writing write;
> void (*cs_control) (u32 command);
> @@ -762,6 +772,378 @@ static void *next_transfer(struct pl022 *pl022)
> }
> return STATE_DONE;
> }
> +
> +/*
> + * This DMA functionality is only compiled in if we have
> + * access to the generic DMA devices/DMA engine.
> + */
> +#ifdef CONFIG_DMADEVICES
> +static void unmap_free_dma_scatter(struct pl022 *pl022)
> +{
> + /* Unmap and free the SG tables */
> + dma_unmap_sg(&pl022->adev->dev, pl022->sgt_tx.sgl,
> + pl022->sgt_tx.nents, DMA_TO_DEVICE);
> + dma_unmap_sg(&pl022->adev->dev, pl022->sgt_rx.sgl,
> + pl022->sgt_rx.nents, DMA_FROM_DEVICE);
> + sg_free_table(&pl022->sgt_rx);
> + sg_free_table(&pl022->sgt_tx);
> +}
> +
> +static void dma_callback(void *data)
> +{
> + struct pl022 *pl022 = data;
> + struct spi_message *msg = pl022->cur_msg;
> +
> + /* Sync in RX buffer to CPU */
> + BUG_ON(!pl022->sgt_rx.sgl);
> + dma_sync_sg_for_cpu(&pl022->adev->dev,
> + pl022->sgt_rx.sgl,
> + pl022->sgt_rx.nents,
> + DMA_FROM_DEVICE);
> +
> +#ifdef VERBOSE_DEBUG
> + /*
> + * Optionally dump out buffers to inspect contents, this is
> + * good if you want to convince yourself that the loopback
> + * read/write contents are the same, when adopting to a new
> + * DMA engine.
> + */
> + {
> + struct scatterlist *sg;
> + unsigned int i;
> +
> + for_each_sg(pl022->sgt_rx.sgl, sg, pl022->sgt_rx.nents, i) {
> + dev_dbg(&pl022->adev->dev, "SPI RX SG ENTRY: %d", i);
> + print_hex_dump(KERN_ERR, "SPI RX: ",
> + DUMP_PREFIX_OFFSET,
> + 16,
> + 1,
> + sg_virt(sg),
> + sg_dma_len(sg),
> + 1);
> + }
> + for_each_sg(pl022->sgt_tx.sgl, sg, pl022->sgt_tx.nents, i) {
> + dev_dbg(&pl022->adev->dev, "SPI TX SG ENTRY: %d", i);
> + print_hex_dump(KERN_ERR, "SPI TX: ",
> + DUMP_PREFIX_OFFSET,
> + 16,
> + 1,
> + sg_virt(sg),
> + sg_dma_len(sg),
> + 1);
> + }
> + }
> +#endif
> +
> + unmap_free_dma_scatter(pl022);
> +
> + /* Update total bytes transfered */
> + msg->actual_length += pl022->cur_transfer->len;
> + if (pl022->cur_transfer->cs_change)
> + pl022->cur_chip->
> + cs_control(SSP_CHIP_DESELECT);
> +
> + /* Move to next transfer */
> + msg->state = next_transfer(pl022);
> + tasklet_schedule(&pl022->pump_transfers);
> +}
> +
> +static void setup_dma_scatter(struct pl022 *pl022,
> + void *buffer,
> + unsigned int length,
> + struct sg_table *sgtab)
> +{
> + struct scatterlist *sg;
> + int bytesleft = length;
> + void *bufp = buffer;
> + int mapbytes;
> + int i;
> +
> + if (buffer) {
> + for_each_sg(sgtab->sgl, sg, sgtab->nents, i) {
> + /*
> + * If there are less bytes left than what fits
> + * in the current page (plus page alignment offset)
> + * we just feed in this, else we stuff in as much
> + * as we can.
> + */
> + if (bytesleft < (PAGE_SIZE - offset_in_page(bufp)))
> + mapbytes = bytesleft;
> + else
> + mapbytes = PAGE_SIZE - offset_in_page(bufp);
> + sg_set_page(sg, virt_to_page(bufp),
> + mapbytes, offset_in_page(bufp));
> + bufp += mapbytes;
> + bytesleft -= mapbytes;
> + dev_dbg(&pl022->adev->dev,
> + "set RX/TX target page @ %p, %d bytes, %d left\n",
> + bufp, mapbytes, bytesleft);
> + }
> + } else {
> + /* Map the dummy buffer on every page */
> + for_each_sg(sgtab->sgl, sg, sgtab->nents, i) {
> + if (bytesleft < PAGE_SIZE)
> + mapbytes = bytesleft;
> + else
> + mapbytes = PAGE_SIZE;
> + sg_set_page(sg, virt_to_page(pl022->dummypage),
> + mapbytes, 0);
> + bytesleft -= mapbytes;
> + dev_dbg(&pl022->adev->dev,
> + "set RX/TX to dummy page %d bytes, %d left\n",
> + mapbytes, bytesleft);
> +
> + }
> + }
> + BUG_ON(bytesleft);
> +}
> +
> +/**
> + * configure_dma - configures the channels for the next transfer
> + * @data: SSP driver's private data structure
> + *
> + */
> +static int configure_dma(struct pl022 *pl022)
> +{
> + struct dma_slave_config rx_conf = {
> + .src_addr = SSP_DR(pl022->phybase),
> + .direction = DMA_FROM_DEVICE,
> + .src_maxburst = pl022->vendor->fifodepth >> 1,
> + };
> + struct dma_slave_config tx_conf = {
> + .dst_addr = SSP_DR(pl022->phybase),
> + .direction = DMA_TO_DEVICE,
> + .dst_maxburst = pl022->vendor->fifodepth >> 1,
> + };
> + unsigned int pages;
> + int ret;
> + int sglen;
> + struct dma_chan *rxchan = pl022->dma_rx_channel;
> + struct dma_chan *txchan = pl022->dma_tx_channel;
> + struct dma_async_tx_descriptor *rxdesc;
> + struct dma_async_tx_descriptor *txdesc;
> + dma_cookie_t cookie;
> +
> + /* Check that the channels are available */
> + if (!rxchan || !txchan)
> + return -ENODEV;
> +
> + switch (pl022->read) {
> + case READING_NULL:
> + /* Use the same as for writing */
> + rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
> + break;
> + case READING_U8:
> + rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
> + break;
> + case READING_U16:
> + rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
> + break;
> + case READING_U32:
> + rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
> + break;
> + }
> +
> + switch (pl022->write) {
> + case WRITING_NULL:
> + /* Use the same as for reading */
> + tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
> + break;
> + case WRITING_U8:
> + tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
> + break;
> + case WRITING_U16:
> + tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
> + break;
> + case WRITING_U32:
> + tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;;
> + break;
> + }
> +
> + /* SPI pecularity: we need to read and write the same width */
> + if (rx_conf.src_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
> + rx_conf.src_addr_width = tx_conf.dst_addr_width;
> + if (tx_conf.dst_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
> + tx_conf.dst_addr_width = rx_conf.src_addr_width;
> + BUG_ON(rx_conf.src_addr_width != tx_conf.dst_addr_width);
> +
> + rxchan->device->device_control(rxchan, DMA_SLAVE_CONFIG,
> + (unsigned long) &rx_conf);
> + txchan->device->device_control(txchan, DMA_SLAVE_CONFIG,
> + (unsigned long) &tx_conf);
> +
> + /* Create sglists for the transfers */
> + pages = (pl022->cur_transfer->len >> PAGE_SHIFT) + 1;
> + dev_dbg(&pl022->adev->dev, "using %d pages for transfer\n", pages);
> +
> + ret = sg_alloc_table(&pl022->sgt_rx, pages, GFP_KERNEL);
> + if (ret)
> + goto err_alloc_rx_sg;
> +
> + ret = sg_alloc_table(&pl022->sgt_tx, pages, GFP_KERNEL);
> + if (ret)
> + goto err_alloc_tx_sg;
> +
> + /* Fill in the scatterlists for the RX+TX buffers */
> + setup_dma_scatter(pl022, pl022->rx,
> + pl022->cur_transfer->len, &pl022->sgt_rx);
> + setup_dma_scatter(pl022, pl022->tx,
> + pl022->cur_transfer->len, &pl022->sgt_tx);
> +
> + /* Map DMA buffers */
> + sglen = dma_map_sg(&pl022->adev->dev, pl022->sgt_rx.sgl,
> + pl022->sgt_rx.nents, DMA_FROM_DEVICE);
> + if (sglen != pages)
> + goto err_rx_sgmap;
> +
> + sglen = dma_map_sg(&pl022->adev->dev, pl022->sgt_tx.sgl,
> + pl022->sgt_tx.nents, DMA_TO_DEVICE);
> + if (sglen != pages)
> + goto err_tx_sgmap;
> +
> + /* Synchronize the TX scatterlist, invalidate buffers, caches etc */
> + dma_sync_sg_for_device(&pl022->adev->dev,
> + pl022->sgt_tx.sgl,
> + pl022->sgt_tx.nents,
> + DMA_TO_DEVICE);
> +
> + /* Send both scatterlists */
> + rxdesc = rxchan->device->device_prep_slave_sg(rxchan,
> + pl022->sgt_rx.sgl,
> + pl022->sgt_rx.nents,
> + DMA_FROM_DEVICE,
> + DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
> + if (!rxdesc)
> + goto err_rxdesc;
> +
> + txdesc = txchan->device->device_prep_slave_sg(txchan,
> + pl022->sgt_tx.sgl,
> + pl022->sgt_tx.nents,
> + DMA_TO_DEVICE,
> + DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
> + if (!txdesc)
> + goto err_txdesc;
> +
> + /* Put the callback on the RX transfer only, that should finish last */
> + rxdesc->callback = dma_callback;
> + rxdesc->callback_param = pl022;
> +
> + /* Submit and fire RX and TX with TX last so we're ready to read! */
> + cookie = rxdesc->tx_submit(rxdesc);
> + if (dma_submit_error(cookie))
> + goto err_submit_rx;
> + cookie = txdesc->tx_submit(txdesc);
> + if (dma_submit_error(cookie))
> + goto err_submit_tx;
> + rxchan->device->device_issue_pending(rxchan);
> + txchan->device->device_issue_pending(txchan);
> +
> + return 0;
> +
> +err_submit_tx:
> +err_submit_rx:
> +err_txdesc:
> + txchan->device->device_control(txchan, DMA_TERMINATE_ALL, 0);
> +err_rxdesc:
> + rxchan->device->device_control(rxchan, DMA_TERMINATE_ALL, 0);
> + dma_unmap_sg(&pl022->adev->dev, pl022->sgt_tx.sgl,
> + pl022->sgt_tx.nents, DMA_TO_DEVICE);
> +err_tx_sgmap:
> + dma_unmap_sg(&pl022->adev->dev, pl022->sgt_rx.sgl,
> + pl022->sgt_tx.nents, DMA_FROM_DEVICE);
> +err_rx_sgmap:
> + sg_free_table(&pl022->sgt_tx);
> +err_alloc_tx_sg:
> + sg_free_table(&pl022->sgt_rx);
> +err_alloc_rx_sg:
> + return -ENOMEM;
> +}
> +
> +static int __init pl022_dma_probe(struct pl022 *pl022)
> +{
> + dma_cap_mask_t mask;
> +
> + /* Try to acquire a generic DMA engine slave channel */
> + dma_cap_zero(mask);
> + dma_cap_set(DMA_SLAVE, mask);
> + /*
> + * We need both RX and TX channels to do DMA, else do none
> + * of them.
> + */
> + pl022->dma_rx_channel = dma_request_channel(mask,
> + pl022->master_info->dma_filter,
> + pl022->master_info->dma_rx_param);
> + if (!pl022->dma_rx_channel) {
> + dev_err(&pl022->adev->dev, "no RX DMA channel!\n");
> + goto err_no_rxchan;
> + }
> +
> + pl022->dma_tx_channel = dma_request_channel(mask,
> + pl022->master_info->dma_filter,
> + pl022->master_info->dma_tx_param);
> + if (!pl022->dma_tx_channel) {
> + dev_err(&pl022->adev->dev, "no TX DMA channel!\n");
> + goto err_no_txchan;
> + }
> +
> + pl022->dummypage = kmalloc(PAGE_SIZE, GFP_KERNEL);
> + if (!pl022->dummypage) {
> + dev_err(&pl022->adev->dev, "no DMA dummypage!\n");
> + goto err_no_dummypage;
> + }
> +
> + dev_info(&pl022->adev->dev, "setup for DMA on RX %s, TX %s\n",
> + dma_chan_name(pl022->dma_rx_channel),
> + dma_chan_name(pl022->dma_tx_channel));
> +
> + return 0;
> +
> +err_no_dummypage:
> + dma_release_channel(pl022->dma_tx_channel);
> +err_no_txchan:
> + dma_release_channel(pl022->dma_rx_channel);
> + pl022->dma_rx_channel = NULL;
> +err_no_rxchan:
> + return -ENODEV;
> +}
> +
> +static void terminate_dma(struct pl022 *pl022)
> +{
> + struct dma_chan *rxchan = pl022->dma_rx_channel;
> + struct dma_chan *txchan = pl022->dma_tx_channel;
> +
> + rxchan->device->device_control(rxchan, DMA_TERMINATE_ALL, 0);
> + txchan->device->device_control(txchan, DMA_TERMINATE_ALL, 0);
> + unmap_free_dma_scatter(pl022);
> +}
> +
> +static void pl022_dma_remove(struct pl022 *pl022)
> +{
> + if (pl022->busy)
> + terminate_dma(pl022);
> + if (pl022->dma_tx_channel)
> + dma_release_channel(pl022->dma_tx_channel);
> + if (pl022->dma_rx_channel)
> + dma_release_channel(pl022->dma_rx_channel);
> + kfree(pl022->dummypage);
> +}
> +
> +#else
> +static inline int configure_dma(struct pl022 *pl022)
> +{
> + return -ENODEV;
> +}
> +
> +static inline int pl022_dma_probe(struct pl022 *pl022)
> +{
> + return 0;
> +}
> +
> +static inline void pl022_dma_remove(struct pl022 *pl022)
> +{
> +}
> +#endif
> +
> /**
> * pl022_interrupt_handler - Interrupt handler for SSP controller
> *
> @@ -793,14 +1175,17 @@ static irqreturn_t pl022_interrupt_handler(int irq, void *dev_id)
> if (unlikely(!irq_status))
> return IRQ_NONE;
>
> - /* This handles the error code interrupts */
> + /*
> + * This handles the FIFO interrupts, the timeout
> + * interrupts are flatly ignored, they cannot be
> + * trusted.
> + */
> if (unlikely(irq_status & SSP_MIS_MASK_RORMIS)) {
> /*
> * Overrun interrupt - bail out since our Data has been
> * corrupted
> */
> - dev_err(&pl022->adev->dev,
> - "FIFO overrun\n");
> + dev_err(&pl022->adev->dev, "FIFO overrun\n");
> if (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RFF)
> dev_err(&pl022->adev->dev,
> "RXFIFO is full\n");
> @@ -895,8 +1280,8 @@ static int set_up_next_transfer(struct pl022 *pl022,
> }
>
> /**
> - * pump_transfers - Tasklet function which schedules next interrupt transfer
> - * when running in interrupt transfer mode.
> + * pump_transfers - Tasklet function which schedules next transfer
> + * when running in interrupt or DMA transfer mode.
> * @data: SSP driver private data structure
> *
> */
> @@ -953,65 +1338,23 @@ static void pump_transfers(unsigned long data)
> }
> /* Flush the FIFOs and let's go! */
> flush(pl022);
> - writew(ENABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
> -}
>
> -/**
> - * NOT IMPLEMENTED
> - * configure_dma - It configures the DMA pipes for DMA transfers
> - * @data: SSP driver's private data structure
> - *
> - */
> -static int configure_dma(void *data)
> -{
> - struct pl022 *pl022 = data;
> - dev_dbg(&pl022->adev->dev, "configure DMA\n");
> - return -ENOTSUPP;
> -}
> -
> -/**
> - * do_dma_transfer - It handles transfers of the current message
> - * if it is DMA xfer.
> - * NOT FULLY IMPLEMENTED
> - * @data: SSP driver's private data structure
> - */
> -static void do_dma_transfer(void *data)
> -{
> - struct pl022 *pl022 = data;
> -
> - if (configure_dma(data)) {
> - dev_dbg(&pl022->adev->dev, "configuration of DMA Failed!\n");
> - goto err_config_dma;
> - }
> -
> - /* TODO: Implememt DMA setup of pipes here */
> -
> - /* Enable target chip, set up transfer */
> - pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
> - if (set_up_next_transfer(pl022, pl022->cur_transfer)) {
> - /* Error path */
> - pl022->cur_msg->state = STATE_ERROR;
> - pl022->cur_msg->status = -EIO;
> - giveback(pl022);
> + if (pl022->cur_chip->enable_dma) {
> + if (configure_dma(pl022)) {
> + dev_dbg(&pl022->adev->dev,
> + "configuration of DMA failed, fall back to interrupt mode\n");
> + goto err_config_dma;
> + }
> return;
> }
> - /* Enable SSP */
> - writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
> - SSP_CR1(pl022->virtbase));
> -
> - /* TODO: Enable the DMA transfer here */
> - return;
>
> - err_config_dma:
> - pl022->cur_msg->state = STATE_ERROR;
> - pl022->cur_msg->status = -EIO;
> - giveback(pl022);
> - return;
> +err_config_dma:
> + writew(ENABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
> }
>
> -static void do_interrupt_transfer(void *data)
> +static void do_interrupt_dma_transfer(struct pl022 *pl022)
> {
> - struct pl022 *pl022 = data;
> + u32 irqflags = ENABLE_ALL_INTERRUPTS;
>
> /* Enable target chip */
> pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
> @@ -1022,15 +1365,26 @@ static void do_interrupt_transfer(void *data)
> giveback(pl022);
> return;
> }
> + /* If we're using DMA, set up DMA here */
> + if (pl022->cur_chip->enable_dma) {
> + /* Configure DMA transfer */
> + if (configure_dma(pl022)) {
> + dev_dbg(&pl022->adev->dev,
> + "configuration of DMA failed, fall back to interrupt mode\n");
> + goto err_config_dma;
> + }
> + /* Disable interrupts in DMA mode, IRQ from DMA controller */
> + irqflags = DISABLE_ALL_INTERRUPTS;
> + }
> +err_config_dma:
> /* Enable SSP, turn on interrupts */
> writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
> SSP_CR1(pl022->virtbase));
> - writew(ENABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
> + writew(irqflags, SSP_IMSC(pl022->virtbase));
> }
>
> -static void do_polling_transfer(void *data)
> +static void do_polling_transfer(struct pl022 *pl022)
> {
> - struct pl022 *pl022 = data;
> struct spi_message *message = NULL;
> struct spi_transfer *transfer = NULL;
> struct spi_transfer *previous = NULL;
> @@ -1100,7 +1454,7 @@ static void do_polling_transfer(void *data)
> *
> * This function checks if there is any spi message in the queue that
> * needs processing and delegate control to appropriate function
> - * do_polling_transfer()/do_interrupt_transfer()/do_dma_transfer()
> + * do_polling_transfer()/do_interrupt_dma_transfer()
> * based on the kind of the transfer
> *
> */
> @@ -1148,10 +1502,8 @@ static void pump_messages(struct work_struct *work)
>
> if (pl022->cur_chip->xfer_type == POLLING_TRANSFER)
> do_polling_transfer(pl022);
> - else if (pl022->cur_chip->xfer_type == INTERRUPT_TRANSFER)
> - do_interrupt_transfer(pl022);
> else
> - do_dma_transfer(pl022);
> + do_interrupt_dma_transfer(pl022);
> }
>
>
> @@ -1466,23 +1818,6 @@ static int calculate_effective_freq(struct pl022 *pl022,
> }
>
> /**
> - * NOT IMPLEMENTED
> - * process_dma_info - Processes the DMA info provided by client drivers
> - * @chip_info: chip info provided by client device
> - * @chip: Runtime state maintained by the SSP controller for each spi device
> - *
> - * This function processes and stores DMA config provided by client driver
> - * into the runtime state maintained by the SSP controller driver
> - */
> -static int process_dma_info(struct pl022_config_chip *chip_info,
> - struct chip_data *chip)
> -{
> - dev_err(chip_info->dev,
> - "cannot process DMA info, DMA not implemented!\n");
> - return -ENOTSUPP;
> -}
> -
> -/**
> * pl022_setup - setup function registered to SPI master framework
> * @spi: spi device which is requesting setup
> *
> @@ -1549,8 +1884,6 @@ static int pl022_setup(struct spi_device *spi)
>
> dev_dbg(&spi->dev, "allocated memory for controller data\n");
>
> - /* Pointer back to the SPI device */
> - chip_info->dev = &spi->dev;
> /*
> * Set controller data default values:
> * Polling is supported by default
> @@ -1576,6 +1909,9 @@ static int pl022_setup(struct spi_device *spi)
> "using user supplied controller_data settings\n");
> }
>
> + /* Pointer back to the SPI device */
> + chip_info->dev = &spi->dev;
> +
> /*
> * We can override with custom divisors, else we use the board
> * frequency setting
> @@ -1634,9 +1970,8 @@ static int pl022_setup(struct spi_device *spi)
> chip->cpsr = 0;
> if ((chip_info->com_mode == DMA_TRANSFER)
> && ((pl022->master_info)->enable_dma)) {
> - chip->enable_dma = 1;
> + chip->enable_dma = true;
> dev_dbg(&spi->dev, "DMA mode set in controller state\n");
> - status = process_dma_info(chip_info, chip);
> if (status < 0)
> goto err_config_params;
> SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED,
> @@ -1644,7 +1979,7 @@ static int pl022_setup(struct spi_device *spi)
> SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED,
> SSP_DMACR_MASK_TXDMAE, 1);
> } else {
> - chip->enable_dma = 0;
> + chip->enable_dma = false;
> dev_dbg(&spi->dev, "DMA mode NOT set in controller state\n");
> SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED,
> SSP_DMACR_MASK_RXDMAE, 0);
> @@ -1770,6 +2105,7 @@ pl022_probe(struct amba_device *adev, struct amba_id *id)
> if (status)
> goto err_no_ioregion;
>
> + pl022->phybase = adev->res.start;
> pl022->virtbase = ioremap(adev->res.start, resource_size(&adev->res));
> if (pl022->virtbase == NULL) {
> status = -ENOMEM;
> @@ -1798,6 +2134,14 @@ pl022_probe(struct amba_device *adev, struct amba_id *id)
> dev_err(&adev->dev, "probe - cannot get IRQ (%d)\n", status);
> goto err_no_irq;
> }
> +
> + /* Get DMA channels */
> + if (platform_info->enable_dma) {
> + status = pl022_dma_probe(pl022);
> + if (status != 0)
> + goto err_no_dma;
> + }
> +
> /* Initialize and start queue */
> status = init_queue(pl022);
> if (status != 0) {
> @@ -1824,6 +2168,8 @@ pl022_probe(struct amba_device *adev, struct amba_id *id)
> err_start_queue:
> err_init_queue:
> destroy_queue(pl022);
> + pl022_dma_remove(pl022);
> + err_no_dma:
> free_irq(adev->irq[0], pl022);
> err_no_irq:
> clk_put(pl022->clk);
> @@ -1854,6 +2200,7 @@ pl022_remove(struct amba_device *adev)
> return status;
> }
> load_ssp_default_config(pl022);
> + pl022_dma_remove(pl022);
> free_irq(adev->irq[0], pl022);
> clk_disable(pl022->clk);
> clk_put(pl022->clk);
> diff --git a/include/linux/amba/pl022.h b/include/linux/amba/pl022.h
> index abf26cc..db6a191 100644
> --- a/include/linux/amba/pl022.h
> +++ b/include/linux/amba/pl022.h
> @@ -228,6 +228,7 @@ enum ssp_chip_select {
> };
>
>
> +struct dma_chan;
> /**
> * struct pl022_ssp_master - device.platform_data for SPI controller devices.
> * @num_chipselect: chipselects are used to distinguish individual
> @@ -235,11 +236,16 @@ enum ssp_chip_select {
> * each slave has a chipselect signal, but it's common that not
> * every chipselect is connected to a slave.
> * @enable_dma: if true enables DMA driven transfers.
> + * @dma_rx_param: parameter to locate an RX DMA channel.
> + * @dma_tx_param: parameter to locate a TX DMA channel.
> */
> struct pl022_ssp_controller {
> u16 bus_id;
> u8 num_chipselect;
> u8 enable_dma:1;
> + bool (*dma_filter)(struct dma_chan *chan, void *filter_param);
> + void *dma_rx_param;
> + void *dma_tx_param;
> };
>
> /**
> --
> 1.6.3.3
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
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