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authorGrant Likely <grant.likely@secretlab.ca>2013-02-09 16:02:44 +0000
committerGrant Likely <grant.likely@secretlab.ca>2013-02-09 16:02:44 +0000
commit0d73299ddf1f4c3ea9f8606b49c4346871a3f139 (patch)
tree5b6a02093f8e9838346536c5805bcc5ff69dba98 /drivers/spi
parent7410e848583f9120dd5f9414629f01bb76b5ee5f (diff)
parenta3496855d9f1948d1b977afe8bd922725ded05d5 (diff)
downloadop-kernel-dev-0d73299ddf1f4c3ea9f8606b49c4346871a3f139.zip
op-kernel-dev-0d73299ddf1f4c3ea9f8606b49c4346871a3f139.tar.gz
Merge branch spi-next from git://git.kernel.org/pub/scm/linux/kernel/git/broonie/misc.git
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Diffstat (limited to 'drivers/spi')
-rw-r--r--drivers/spi/Kconfig13
-rw-r--r--drivers/spi/Makefile5
-rw-r--r--drivers/spi/spi-pxa2xx-dma.c392
-rw-r--r--drivers/spi/spi-pxa2xx-pxadma.c490
-rw-r--r--drivers/spi/spi-pxa2xx.c908
-rw-r--r--drivers/spi/spi-pxa2xx.h221
6 files changed, 1451 insertions, 578 deletions
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index a90393d..e79884e9 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -297,9 +297,20 @@ config SPI_PPC4xx
help
This selects a driver for the PPC4xx SPI Controller.
+config SPI_PXA2XX_PXADMA
+ bool "PXA2xx SSP legacy PXA DMA API support"
+ depends on SPI_PXA2XX && ARCH_PXA
+ help
+ Enable PXA private legacy DMA API support. Note that this is
+ deprecated in favor of generic DMA engine API.
+
+config SPI_PXA2XX_DMA
+ def_bool y
+ depends on SPI_PXA2XX && !SPI_PXA2XX_PXADMA
+
config SPI_PXA2XX
tristate "PXA2xx SSP SPI master"
- depends on ARCH_PXA || PCI
+ depends on ARCH_PXA || PCI || ACPI
select PXA_SSP if ARCH_PXA
help
This enables using a PXA2xx or Sodaville SSP port as a SPI master
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index 64e970b..e53c309 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -47,7 +47,10 @@ obj-$(CONFIG_SPI_OMAP24XX) += spi-omap2-mcspi.o
obj-$(CONFIG_SPI_ORION) += spi-orion.o
obj-$(CONFIG_SPI_PL022) += spi-pl022.o
obj-$(CONFIG_SPI_PPC4xx) += spi-ppc4xx.o
-obj-$(CONFIG_SPI_PXA2XX) += spi-pxa2xx.o
+spi-pxa2xx-platform-objs := spi-pxa2xx.o
+spi-pxa2xx-platform-$(CONFIG_SPI_PXA2XX_PXADMA) += spi-pxa2xx-pxadma.o
+spi-pxa2xx-platform-$(CONFIG_SPI_PXA2XX_DMA) += spi-pxa2xx-dma.o
+obj-$(CONFIG_SPI_PXA2XX) += spi-pxa2xx-platform.o
obj-$(CONFIG_SPI_PXA2XX_PCI) += spi-pxa2xx-pci.o
obj-$(CONFIG_SPI_RSPI) += spi-rspi.o
obj-$(CONFIG_SPI_S3C24XX) += spi-s3c24xx-hw.o
diff --git a/drivers/spi/spi-pxa2xx-dma.c b/drivers/spi/spi-pxa2xx-dma.c
new file mode 100644
index 0000000..c735c5a
--- /dev/null
+++ b/drivers/spi/spi-pxa2xx-dma.c
@@ -0,0 +1,392 @@
+/*
+ * PXA2xx SPI DMA engine support.
+ *
+ * Copyright (C) 2013, Intel Corporation
+ * Author: Mika Westerberg <mika.westerberg@linux.intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/pxa2xx_ssp.h>
+#include <linux/scatterlist.h>
+#include <linux/sizes.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/pxa2xx_spi.h>
+
+#include "spi-pxa2xx.h"
+
+static int pxa2xx_spi_map_dma_buffer(struct driver_data *drv_data,
+ enum dma_data_direction dir)
+{
+ int i, nents, len = drv_data->len;
+ struct scatterlist *sg;
+ struct device *dmadev;
+ struct sg_table *sgt;
+ void *buf, *pbuf;
+
+ /*
+ * Some DMA controllers have problems transferring buffers that are
+ * not multiple of 4 bytes. So we truncate the transfer so that it
+ * is suitable for such controllers, and handle the trailing bytes
+ * manually after the DMA completes.
+ *
+ * REVISIT: It would be better if this information could be
+ * retrieved directly from the DMA device in a similar way than
+ * ->copy_align etc. is done.
+ */
+ len = ALIGN(drv_data->len, 4);
+
+ if (dir == DMA_TO_DEVICE) {
+ dmadev = drv_data->tx_chan->device->dev;
+ sgt = &drv_data->tx_sgt;
+ buf = drv_data->tx;
+ drv_data->tx_map_len = len;
+ } else {
+ dmadev = drv_data->rx_chan->device->dev;
+ sgt = &drv_data->rx_sgt;
+ buf = drv_data->rx;
+ drv_data->rx_map_len = len;
+ }
+
+ nents = DIV_ROUND_UP(len, SZ_2K);
+ if (nents != sgt->nents) {
+ int ret;
+
+ sg_free_table(sgt);
+ ret = sg_alloc_table(sgt, nents, GFP_KERNEL);
+ if (ret)
+ return ret;
+ }
+
+ pbuf = buf;
+ for_each_sg(sgt->sgl, sg, sgt->nents, i) {
+ size_t bytes = min_t(size_t, len, SZ_2K);
+
+ if (buf)
+ sg_set_buf(sg, pbuf, bytes);
+ else
+ sg_set_buf(sg, drv_data->dummy, bytes);
+
+ pbuf += bytes;
+ len -= bytes;
+ }
+
+ nents = dma_map_sg(dmadev, sgt->sgl, sgt->nents, dir);
+ if (!nents)
+ return -ENOMEM;
+
+ return nents;
+}
+
+static void pxa2xx_spi_unmap_dma_buffer(struct driver_data *drv_data,
+ enum dma_data_direction dir)
+{
+ struct device *dmadev;
+ struct sg_table *sgt;
+
+ if (dir == DMA_TO_DEVICE) {
+ dmadev = drv_data->tx_chan->device->dev;
+ sgt = &drv_data->tx_sgt;
+ } else {
+ dmadev = drv_data->rx_chan->device->dev;
+ sgt = &drv_data->rx_sgt;
+ }
+
+ dma_unmap_sg(dmadev, sgt->sgl, sgt->nents, dir);
+}
+
+static void pxa2xx_spi_unmap_dma_buffers(struct driver_data *drv_data)
+{
+ if (!drv_data->dma_mapped)
+ return;
+
+ pxa2xx_spi_unmap_dma_buffer(drv_data, DMA_FROM_DEVICE);
+ pxa2xx_spi_unmap_dma_buffer(drv_data, DMA_TO_DEVICE);
+
+ drv_data->dma_mapped = 0;
+}
+
+static void pxa2xx_spi_dma_transfer_complete(struct driver_data *drv_data,
+ bool error)
+{
+ struct spi_message *msg = drv_data->cur_msg;
+
+ /*
+ * It is possible that one CPU is handling ROR interrupt and other
+ * just gets DMA completion. Calling pump_transfers() twice for the
+ * same transfer leads to problems thus we prevent concurrent calls
+ * by using ->dma_running.
+ */
+ if (atomic_dec_and_test(&drv_data->dma_running)) {
+ void __iomem *reg = drv_data->ioaddr;
+
+ /*
+ * If the other CPU is still handling the ROR interrupt we
+ * might not know about the error yet. So we re-check the
+ * ROR bit here before we clear the status register.
+ */
+ if (!error) {
+ u32 status = read_SSSR(reg) & drv_data->mask_sr;
+ error = status & SSSR_ROR;
+ }
+
+ /* Clear status & disable interrupts */
+ write_SSCR1(read_SSCR1(reg) & ~drv_data->dma_cr1, reg);
+ write_SSSR_CS(drv_data, drv_data->clear_sr);
+ if (!pxa25x_ssp_comp(drv_data))
+ write_SSTO(0, reg);
+
+ if (!error) {
+ pxa2xx_spi_unmap_dma_buffers(drv_data);
+
+ /* Handle the last bytes of unaligned transfer */
+ drv_data->tx += drv_data->tx_map_len;
+ drv_data->write(drv_data);
+
+ drv_data->rx += drv_data->rx_map_len;
+ drv_data->read(drv_data);
+
+ msg->actual_length += drv_data->len;
+ msg->state = pxa2xx_spi_next_transfer(drv_data);
+ } else {
+ /* In case we got an error we disable the SSP now */
+ write_SSCR0(read_SSCR0(reg) & ~SSCR0_SSE, reg);
+
+ msg->state = ERROR_STATE;
+ }
+
+ tasklet_schedule(&drv_data->pump_transfers);
+ }
+}
+
+static void pxa2xx_spi_dma_callback(void *data)
+{
+ pxa2xx_spi_dma_transfer_complete(data, false);
+}
+
+static struct dma_async_tx_descriptor *
+pxa2xx_spi_dma_prepare_one(struct driver_data *drv_data,
+ enum dma_transfer_direction dir)
+{
+ struct pxa2xx_spi_master *pdata = drv_data->master_info;
+ struct chip_data *chip = drv_data->cur_chip;
+ enum dma_slave_buswidth width;
+ struct dma_slave_config cfg;
+ struct dma_chan *chan;
+ struct sg_table *sgt;
+ int nents, ret;
+
+ switch (drv_data->n_bytes) {
+ case 1:
+ width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+ break;
+ case 2:
+ width = DMA_SLAVE_BUSWIDTH_2_BYTES;
+ break;
+ default:
+ width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+ break;
+ }
+
+ memset(&cfg, 0, sizeof(cfg));
+ cfg.direction = dir;
+
+ if (dir == DMA_MEM_TO_DEV) {
+ cfg.dst_addr = drv_data->ssdr_physical;
+ cfg.dst_addr_width = width;
+ cfg.dst_maxburst = chip->dma_burst_size;
+ cfg.slave_id = pdata->tx_slave_id;
+
+ sgt = &drv_data->tx_sgt;
+ nents = drv_data->tx_nents;
+ chan = drv_data->tx_chan;
+ } else {
+ cfg.src_addr = drv_data->ssdr_physical;
+ cfg.src_addr_width = width;
+ cfg.src_maxburst = chip->dma_burst_size;
+ cfg.slave_id = pdata->rx_slave_id;
+
+ sgt = &drv_data->rx_sgt;
+ nents = drv_data->rx_nents;
+ chan = drv_data->rx_chan;
+ }
+
+ ret = dmaengine_slave_config(chan, &cfg);
+ if (ret) {
+ dev_warn(&drv_data->pdev->dev, "DMA slave config failed\n");
+ return NULL;
+ }
+
+ return dmaengine_prep_slave_sg(chan, sgt->sgl, nents, dir,
+ DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+}
+
+static bool pxa2xx_spi_dma_filter(struct dma_chan *chan, void *param)
+{
+ const struct pxa2xx_spi_master *pdata = param;
+
+ return chan->chan_id == pdata->tx_chan_id ||
+ chan->chan_id == pdata->rx_chan_id;
+}
+
+bool pxa2xx_spi_dma_is_possible(size_t len)
+{
+ return len <= MAX_DMA_LEN;
+}
+
+int pxa2xx_spi_map_dma_buffers(struct driver_data *drv_data)
+{
+ const struct chip_data *chip = drv_data->cur_chip;
+ int ret;
+
+ if (!chip->enable_dma)
+ return 0;
+
+ /* Don't bother with DMA if we can't do even a single burst */
+ if (drv_data->len < chip->dma_burst_size)
+ return 0;
+
+ ret = pxa2xx_spi_map_dma_buffer(drv_data, DMA_TO_DEVICE);
+ if (ret <= 0) {
+ dev_warn(&drv_data->pdev->dev, "failed to DMA map TX\n");
+ return 0;
+ }
+
+ drv_data->tx_nents = ret;
+
+ ret = pxa2xx_spi_map_dma_buffer(drv_data, DMA_FROM_DEVICE);
+ if (ret <= 0) {
+ pxa2xx_spi_unmap_dma_buffer(drv_data, DMA_TO_DEVICE);
+ dev_warn(&drv_data->pdev->dev, "failed to DMA map RX\n");
+ return 0;
+ }
+
+ drv_data->rx_nents = ret;
+ return 1;
+}
+
+irqreturn_t pxa2xx_spi_dma_transfer(struct driver_data *drv_data)
+{
+ u32 status;
+
+ status = read_SSSR(drv_data->ioaddr) & drv_data->mask_sr;
+ if (status & SSSR_ROR) {
+ dev_err(&drv_data->pdev->dev, "FIFO overrun\n");
+
+ dmaengine_terminate_all(drv_data->rx_chan);
+ dmaengine_terminate_all(drv_data->tx_chan);
+
+ pxa2xx_spi_dma_transfer_complete(drv_data, true);
+ return IRQ_HANDLED;
+ }
+
+ return IRQ_NONE;
+}
+
+int pxa2xx_spi_dma_prepare(struct driver_data *drv_data, u32 dma_burst)
+{
+ struct dma_async_tx_descriptor *tx_desc, *rx_desc;
+
+ tx_desc = pxa2xx_spi_dma_prepare_one(drv_data, DMA_MEM_TO_DEV);
+ if (!tx_desc) {
+ dev_err(&drv_data->pdev->dev,
+ "failed to get DMA TX descriptor\n");
+ return -EBUSY;
+ }
+
+ rx_desc = pxa2xx_spi_dma_prepare_one(drv_data, DMA_DEV_TO_MEM);
+ if (!rx_desc) {
+ dev_err(&drv_data->pdev->dev,
+ "failed to get DMA RX descriptor\n");
+ return -EBUSY;
+ }
+
+ /* We are ready when RX completes */
+ rx_desc->callback = pxa2xx_spi_dma_callback;
+ rx_desc->callback_param = drv_data;
+
+ dmaengine_submit(rx_desc);
+ dmaengine_submit(tx_desc);
+ return 0;
+}
+
+void pxa2xx_spi_dma_start(struct driver_data *drv_data)
+{
+ dma_async_issue_pending(drv_data->rx_chan);
+ dma_async_issue_pending(drv_data->tx_chan);
+
+ atomic_set(&drv_data->dma_running, 1);
+}
+
+int pxa2xx_spi_dma_setup(struct driver_data *drv_data)
+{
+ struct pxa2xx_spi_master *pdata = drv_data->master_info;
+ dma_cap_mask_t mask;
+
+ dma_cap_zero(mask);
+ dma_cap_set(DMA_SLAVE, mask);
+
+ drv_data->dummy = devm_kzalloc(&drv_data->pdev->dev, SZ_2K, GFP_KERNEL);
+ if (!drv_data->dummy)
+ return -ENOMEM;
+
+ drv_data->tx_chan = dma_request_channel(mask, pxa2xx_spi_dma_filter,
+ pdata);
+ if (!drv_data->tx_chan)
+ return -ENODEV;
+
+ drv_data->rx_chan = dma_request_channel(mask, pxa2xx_spi_dma_filter,
+ pdata);
+ if (!drv_data->rx_chan) {
+ dma_release_channel(drv_data->tx_chan);
+ drv_data->tx_chan = NULL;
+ return -ENODEV;
+ }
+
+ return 0;
+}
+
+void pxa2xx_spi_dma_release(struct driver_data *drv_data)
+{
+ if (drv_data->rx_chan) {
+ dmaengine_terminate_all(drv_data->rx_chan);
+ dma_release_channel(drv_data->rx_chan);
+ sg_free_table(&drv_data->rx_sgt);
+ drv_data->rx_chan = NULL;
+ }
+ if (drv_data->tx_chan) {
+ dmaengine_terminate_all(drv_data->tx_chan);
+ dma_release_channel(drv_data->tx_chan);
+ sg_free_table(&drv_data->tx_sgt);
+ drv_data->tx_chan = NULL;
+ }
+}
+
+void pxa2xx_spi_dma_resume(struct driver_data *drv_data)
+{
+}
+
+int pxa2xx_spi_set_dma_burst_and_threshold(struct chip_data *chip,
+ struct spi_device *spi,
+ u8 bits_per_word, u32 *burst_code,
+ u32 *threshold)
+{
+ struct pxa2xx_spi_chip *chip_info = spi->controller_data;
+
+ /*
+ * If the DMA burst size is given in chip_info we use that,
+ * otherwise we use the default. Also we use the default FIFO
+ * thresholds for now.
+ */
+ *burst_code = chip_info ? chip_info->dma_burst_size : 16;
+ *threshold = SSCR1_RxTresh(RX_THRESH_DFLT)
+ | SSCR1_TxTresh(TX_THRESH_DFLT);
+
+ return 0;
+}
diff --git a/drivers/spi/spi-pxa2xx-pxadma.c b/drivers/spi/spi-pxa2xx-pxadma.c
new file mode 100644
index 0000000..2916efc
--- /dev/null
+++ b/drivers/spi/spi-pxa2xx-pxadma.c
@@ -0,0 +1,490 @@
+/*
+ * PXA2xx SPI private DMA support.
+ *
+ * Copyright (C) 2005 Stephen Street / StreetFire Sound Labs
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/pxa2xx_ssp.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/pxa2xx_spi.h>
+
+#include "spi-pxa2xx.h"
+
+#define DMA_INT_MASK (DCSR_ENDINTR | DCSR_STARTINTR | DCSR_BUSERR)
+#define RESET_DMA_CHANNEL (DCSR_NODESC | DMA_INT_MASK)
+
+bool pxa2xx_spi_dma_is_possible(size_t len)
+{
+ /* Try to map dma buffer and do a dma transfer if successful, but
+ * only if the length is non-zero and less than MAX_DMA_LEN.
+ *
+ * Zero-length non-descriptor DMA is illegal on PXA2xx; force use
+ * of PIO instead. Care is needed above because the transfer may
+ * have have been passed with buffers that are already dma mapped.
+ * A zero-length transfer in PIO mode will not try to write/read
+ * to/from the buffers
+ *
+ * REVISIT large transfers are exactly where we most want to be
+ * using DMA. If this happens much, split those transfers into
+ * multiple DMA segments rather than forcing PIO.
+ */
+ return len > 0 && len <= MAX_DMA_LEN;
+}
+
+int pxa2xx_spi_map_dma_buffers(struct driver_data *drv_data)
+{
+ struct spi_message *msg = drv_data->cur_msg;
+ struct device *dev = &msg->spi->dev;
+
+ if (!drv_data->cur_chip->enable_dma)
+ return 0;
+
+ if (msg->is_dma_mapped)
+ return drv_data->rx_dma && drv_data->tx_dma;
+
+ if (!IS_DMA_ALIGNED(drv_data->rx) || !IS_DMA_ALIGNED(drv_data->tx))
+ return 0;
+
+ /* Modify setup if rx buffer is null */
+ if (drv_data->rx == NULL) {
+ *drv_data->null_dma_buf = 0;
+ drv_data->rx = drv_data->null_dma_buf;
+ drv_data->rx_map_len = 4;
+ } else
+ drv_data->rx_map_len = drv_data->len;
+
+
+ /* Modify setup if tx buffer is null */
+ if (drv_data->tx == NULL) {
+ *drv_data->null_dma_buf = 0;
+ drv_data->tx = drv_data->null_dma_buf;
+ drv_data->tx_map_len = 4;
+ } else
+ drv_data->tx_map_len = drv_data->len;
+
+ /* Stream map the tx buffer. Always do DMA_TO_DEVICE first
+ * so we flush the cache *before* invalidating it, in case
+ * the tx and rx buffers overlap.
+ */
+ drv_data->tx_dma = dma_map_single(dev, drv_data->tx,
+ drv_data->tx_map_len, DMA_TO_DEVICE);
+ if (dma_mapping_error(dev, drv_data->tx_dma))
+ return 0;
+
+ /* Stream map the rx buffer */
+ drv_data->rx_dma = dma_map_single(dev, drv_data->rx,
+ drv_data->rx_map_len, DMA_FROM_DEVICE);
+ if (dma_mapping_error(dev, drv_data->rx_dma)) {
+ dma_unmap_single(dev, drv_data->tx_dma,
+ drv_data->tx_map_len, DMA_TO_DEVICE);
+ return 0;
+ }
+
+ return 1;
+}
+
+static void pxa2xx_spi_unmap_dma_buffers(struct driver_data *drv_data)
+{
+ struct device *dev;
+
+ if (!drv_data->dma_mapped)
+ return;
+
+ if (!drv_data->cur_msg->is_dma_mapped) {
+ dev = &drv_data->cur_msg->spi->dev;
+ dma_unmap_single(dev, drv_data->rx_dma,
+ drv_data->rx_map_len, DMA_FROM_DEVICE);
+ dma_unmap_single(dev, drv_data->tx_dma,
+ drv_data->tx_map_len, DMA_TO_DEVICE);
+ }
+
+ drv_data->dma_mapped = 0;
+}
+
+static int wait_ssp_rx_stall(void const __iomem *ioaddr)
+{
+ unsigned long limit = loops_per_jiffy << 1;
+
+ while ((read_SSSR(ioaddr) & SSSR_BSY) && --limit)
+ cpu_relax();
+
+ return limit;
+}
+
+static int wait_dma_channel_stop(int channel)
+{
+ unsigned long limit = loops_per_jiffy << 1;
+
+ while (!(DCSR(channel) & DCSR_STOPSTATE) && --limit)
+ cpu_relax();
+
+ return limit;
+}
+
+static void pxa2xx_spi_dma_error_stop(struct driver_data *drv_data,
+ const char *msg)
+{
+ void __iomem *reg = drv_data->ioaddr;
+
+ /* Stop and reset */
+ DCSR(drv_data->rx_channel) = RESET_DMA_CHANNEL;
+ DCSR(drv_data->tx_channel) = RESET_DMA_CHANNEL;
+ write_SSSR_CS(drv_data, drv_data->clear_sr);
+ write_SSCR1(read_SSCR1(reg) & ~drv_data->dma_cr1, reg);
+ if (!pxa25x_ssp_comp(drv_data))
+ write_SSTO(0, reg);
+ pxa2xx_spi_flush(drv_data);
+ write_SSCR0(read_SSCR0(reg) & ~SSCR0_SSE, reg);
+
+ pxa2xx_spi_unmap_dma_buffers(drv_data);
+
+ dev_err(&drv_data->pdev->dev, "%s\n", msg);
+
+ drv_data->cur_msg->state = ERROR_STATE;
+ tasklet_schedule(&drv_data->pump_transfers);
+}
+
+static void pxa2xx_spi_dma_transfer_complete(struct driver_data *drv_data)
+{
+ void __iomem *reg = drv_data->ioaddr;
+ struct spi_message *msg = drv_data->cur_msg;
+
+ /* Clear and disable interrupts on SSP and DMA channels*/
+ write_SSCR1(read_SSCR1(reg) & ~drv_data->dma_cr1, reg);
+ write_SSSR_CS(drv_data, drv_data->clear_sr);
+ DCSR(drv_data->tx_channel) = RESET_DMA_CHANNEL;
+ DCSR(drv_data->rx_channel) = RESET_DMA_CHANNEL;
+
+ if (wait_dma_channel_stop(drv_data->rx_channel) == 0)
+ dev_err(&drv_data->pdev->dev,
+ "dma_handler: dma rx channel stop failed\n");
+
+ if (wait_ssp_rx_stall(drv_data->ioaddr) == 0)
+ dev_err(&drv_data->pdev->dev,
+ "dma_transfer: ssp rx stall failed\n");
+
+ pxa2xx_spi_unmap_dma_buffers(drv_data);
+
+ /* update the buffer pointer for the amount completed in dma */
+ drv_data->rx += drv_data->len -
+ (DCMD(drv_data->rx_channel) & DCMD_LENGTH);
+
+ /* read trailing data from fifo, it does not matter how many
+ * bytes are in the fifo just read until buffer is full
+ * or fifo is empty, which ever occurs first */
+ drv_data->read(drv_data);
+
+ /* return count of what was actually read */
+ msg->actual_length += drv_data->len -
+ (drv_data->rx_end - drv_data->rx);
+
+ /* Transfer delays and chip select release are
+ * handled in pump_transfers or giveback
+ */
+
+ /* Move to next transfer */
+ msg->state = pxa2xx_spi_next_transfer(drv_data);
+
+ /* Schedule transfer tasklet */
+ tasklet_schedule(&drv_data->pump_transfers);
+}
+
+void pxa2xx_spi_dma_handler(int channel, void *data)
+{
+ struct driver_data *drv_data = data;
+ u32 irq_status = DCSR(channel) & DMA_INT_MASK;
+
+ if (irq_status & DCSR_BUSERR) {
+
+ if (channel == drv_data->tx_channel)
+ pxa2xx_spi_dma_error_stop(drv_data,
+ "dma_handler: bad bus address on tx channel");
+ else
+ pxa2xx_spi_dma_error_stop(drv_data,
+ "dma_handler: bad bus address on rx channel");
+ return;
+ }
+
+ /* PXA255x_SSP has no timeout interrupt, wait for tailing bytes */
+ if ((channel == drv_data->tx_channel)
+ && (irq_status & DCSR_ENDINTR)
+ && (drv_data->ssp_type == PXA25x_SSP)) {
+
+ /* Wait for rx to stall */
+ if (wait_ssp_rx_stall(drv_data->ioaddr) == 0)
+ dev_err(&drv_data->pdev->dev,
+ "dma_handler: ssp rx stall failed\n");
+
+ /* finish this transfer, start the next */
+ pxa2xx_spi_dma_transfer_complete(drv_data);
+ }
+}
+
+irqreturn_t pxa2xx_spi_dma_transfer(struct driver_data *drv_data)
+{
+ u32 irq_status;
+ void __iomem *reg = drv_data->ioaddr;
+
+ irq_status = read_SSSR(reg) & drv_data->mask_sr;
+ if (irq_status & SSSR_ROR) {
+ pxa2xx_spi_dma_error_stop(drv_data,
+ "dma_transfer: fifo overrun");
+ return IRQ_HANDLED;
+ }
+
+ /* Check for false positive timeout */
+ if ((irq_status & SSSR_TINT)
+ && (DCSR(drv_data->tx_channel) & DCSR_RUN)) {
+ write_SSSR(SSSR_TINT, reg);
+ return IRQ_HANDLED;
+ }
+
+ if (irq_status & SSSR_TINT || drv_data->rx == drv_data->rx_end) {
+
+ /* Clear and disable timeout interrupt, do the rest in
+ * dma_transfer_complete */
+ if (!pxa25x_ssp_comp(drv_data))
+ write_SSTO(0, reg);
+
+ /* finish this transfer, start the next */
+ pxa2xx_spi_dma_transfer_complete(drv_data);
+
+ return IRQ_HANDLED;
+ }
+
+ /* Opps problem detected */
+ return IRQ_NONE;
+}
+
+int pxa2xx_spi_dma_prepare(struct driver_data *drv_data, u32 dma_burst)
+{
+ u32 dma_width;
+
+ switch (drv_data->n_bytes) {
+ case 1:
+ dma_width = DCMD_WIDTH1;
+ break;
+ case 2:
+ dma_width = DCMD_WIDTH2;
+ break;
+ default:
+ dma_width = DCMD_WIDTH4;
+ break;
+ }
+
+ /* Setup rx DMA Channel */
+ DCSR(drv_data->rx_channel) = RESET_DMA_CHANNEL;
+ DSADR(drv_data->rx_channel) = drv_data->ssdr_physical;
+ DTADR(drv_data->rx_channel) = drv_data->rx_dma;
+ if (drv_data->rx == drv_data->null_dma_buf)
+ /* No target address increment */
+ DCMD(drv_data->rx_channel) = DCMD_FLOWSRC
+ | dma_width
+ | dma_burst
+ | drv_data->len;
+ else
+ DCMD(drv_data->rx_channel) = DCMD_INCTRGADDR
+ | DCMD_FLOWSRC
+ | dma_width
+ | dma_burst
+ | drv_data->len;
+
+ /* Setup tx DMA Channel */
+ DCSR(drv_data->tx_channel) = RESET_DMA_CHANNEL;
+ DSADR(drv_data->tx_channel) = drv_data->tx_dma;
+ DTADR(drv_data->tx_channel) = drv_data->ssdr_physical;
+ if (drv_data->tx == drv_data->null_dma_buf)
+ /* No source address increment */
+ DCMD(drv_data->tx_channel) = DCMD_FLOWTRG
+ | dma_width
+ | dma_burst
+ | drv_data->len;
+ else
+ DCMD(drv_data->tx_channel) = DCMD_INCSRCADDR
+ | DCMD_FLOWTRG
+ | dma_width
+ | dma_burst
+ | drv_data->len;
+
+ /* Enable dma end irqs on SSP to detect end of transfer */
+ if (drv_data->ssp_type == PXA25x_SSP)
+ DCMD(drv_data->tx_channel) |= DCMD_ENDIRQEN;
+
+ return 0;
+}
+
+void pxa2xx_spi_dma_start(struct driver_data *drv_data)
+{
+ DCSR(drv_data->rx_channel) |= DCSR_RUN;
+ DCSR(drv_data->tx_channel) |= DCSR_RUN;
+}
+
+int pxa2xx_spi_dma_setup(struct driver_data *drv_data)
+{
+ struct device *dev = &drv_data->pdev->dev;
+ struct ssp_device *ssp = drv_data->ssp;
+
+ /* Get two DMA channels (rx and tx) */
+ drv_data->rx_channel = pxa_request_dma("pxa2xx_spi_ssp_rx",
+ DMA_PRIO_HIGH,
+ pxa2xx_spi_dma_handler,
+ drv_data);
+ if (drv_data->rx_channel < 0) {
+ dev_err(dev, "problem (%d) requesting rx channel\n",
+ drv_data->rx_channel);
+ return -ENODEV;
+ }
+ drv_data->tx_channel = pxa_request_dma("pxa2xx_spi_ssp_tx",
+ DMA_PRIO_MEDIUM,
+ pxa2xx_spi_dma_handler,
+ drv_data);
+ if (drv_data->tx_channel < 0) {
+ dev_err(dev, "problem (%d) requesting tx channel\n",
+ drv_data->tx_channel);
+ pxa_free_dma(drv_data->rx_channel);
+ return -ENODEV;
+ }
+
+ DRCMR(ssp->drcmr_rx) = DRCMR_MAPVLD | drv_data->rx_channel;
+ DRCMR(ssp->drcmr_tx) = DRCMR_MAPVLD | drv_data->tx_channel;
+
+ return 0;
+}
+
+void pxa2xx_spi_dma_release(struct driver_data *drv_data)
+{
+ struct ssp_device *ssp = drv_data->ssp;
+
+ DRCMR(ssp->drcmr_rx) = 0;
+ DRCMR(ssp->drcmr_tx) = 0;
+
+ if (drv_data->tx_channel != 0)
+ pxa_free_dma(drv_data->tx_channel);
+ if (drv_data->rx_channel != 0)
+ pxa_free_dma(drv_data->rx_channel);
+}
+
+void pxa2xx_spi_dma_resume(struct driver_data *drv_data)
+{
+ if (drv_data->rx_channel != -1)
+ DRCMR(drv_data->ssp->drcmr_rx) =
+ DRCMR_MAPVLD | drv_data->rx_channel;
+ if (drv_data->tx_channel != -1)
+ DRCMR(drv_data->ssp->drcmr_tx) =
+ DRCMR_MAPVLD | drv_data->tx_channel;
+}
+
+int pxa2xx_spi_set_dma_burst_and_threshold(struct chip_data *chip,
+ struct spi_device *spi,
+ u8 bits_per_word, u32 *burst_code,
+ u32 *threshold)
+{
+ struct pxa2xx_spi_chip *chip_info =
+ (struct pxa2xx_spi_chip *)spi->controller_data;
+ int bytes_per_word;
+ int burst_bytes;
+ int thresh_words;
+ int req_burst_size;
+ int retval = 0;
+
+ /* Set the threshold (in registers) to equal the same amount of data
+ * as represented by burst size (in bytes). The computation below
+ * is (burst_size rounded up to nearest 8 byte, word or long word)
+ * divided by (bytes/register); the tx threshold is the inverse of
+ * the rx, so that there will always be enough data in the rx fifo
+ * to satisfy a burst, and there will always be enough space in the
+ * tx fifo to accept a burst (a tx burst will overwrite the fifo if
+ * there is not enough space), there must always remain enough empty
+ * space in the rx fifo for any data loaded to the tx fifo.
+ * Whenever burst_size (in bytes) equals bits/word, the fifo threshold
+ * will be 8, or half the fifo;
+ * The threshold can only be set to 2, 4 or 8, but not 16, because
+ * to burst 16 to the tx fifo, the fifo would have to be empty;
+ * however, the minimum fifo trigger level is 1, and the tx will
+ * request service when the fifo is at this level, with only 15 spaces.
+ */
+
+ /* find bytes/word */
+ if (bits_per_word <= 8)
+ bytes_per_word = 1;
+ else if (bits_per_word <= 16)
+ bytes_per_word = 2;
+ else
+ bytes_per_word = 4;
+
+ /* use struct pxa2xx_spi_chip->dma_burst_size if available */
+ if (chip_info)
+ req_burst_size = chip_info->dma_burst_size;
+ else {
+ switch (chip->dma_burst_size) {
+ default:
+ /* if the default burst size is not set,
+ * do it now */
+ chip->dma_burst_size = DCMD_BURST8;
+ case DCMD_BURST8:
+ req_burst_size = 8;
+ break;
+ case DCMD_BURST16:
+ req_burst_size = 16;
+ break;
+ case DCMD_BURST32:
+ req_burst_size = 32;
+ break;
+ }
+ }
+ if (req_burst_size <= 8) {
+ *burst_code = DCMD_BURST8;
+ burst_bytes = 8;
+ } else if (req_burst_size <= 16) {
+ if (bytes_per_word == 1) {
+ /* don't burst more than 1/2 the fifo */
+ *burst_code = DCMD_BURST8;
+ burst_bytes = 8;
+ retval = 1;
+ } else {
+ *burst_code = DCMD_BURST16;
+ burst_bytes = 16;
+ }
+ } else {
+ if (bytes_per_word == 1) {
+ /* don't burst more than 1/2 the fifo */
+ *burst_code = DCMD_BURST8;
+ burst_bytes = 8;
+ retval = 1;
+ } else if (bytes_per_word == 2) {
+ /* don't burst more than 1/2 the fifo */
+ *burst_code = DCMD_BURST16;
+ burst_bytes = 16;
+ retval = 1;
+ } else {
+ *burst_code = DCMD_BURST32;
+ burst_bytes = 32;
+ }
+ }
+
+ thresh_words = burst_bytes / bytes_per_word;
+
+ /* thresh_words will be between 2 and 8 */
+ *threshold = (SSCR1_RxTresh(thresh_words) & SSCR1_RFT)
+ | (SSCR1_TxTresh(16-thresh_words) & SSCR1_TFT);
+
+ return retval;
+}
diff --git a/drivers/spi/spi-pxa2xx.c b/drivers/spi/spi-pxa2xx.c
index 304cf6e..90b27a3 100644
--- a/drivers/spi/spi-pxa2xx.c
+++ b/drivers/spi/spi-pxa2xx.c
@@ -1,5 +1,6 @@
/*
* Copyright (C) 2005 Stephen Street / StreetFire Sound Labs
+ * Copyright (C) 2013, Intel Corporation
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@@ -24,18 +25,20 @@
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/spi/pxa2xx_spi.h>
-#include <linux/dma-mapping.h>
#include <linux/spi/spi.h>
#include <linux/workqueue.h>
#include <linux/delay.h>
#include <linux/gpio.h>
#include <linux/slab.h>
#include <linux/clk.h>
+#include <linux/pm_runtime.h>
+#include <linux/acpi.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/delay.h>
+#include "spi-pxa2xx.h"
MODULE_AUTHOR("Stephen Street");
MODULE_DESCRIPTION("PXA2xx SSP SPI Controller");
@@ -46,12 +49,6 @@ MODULE_ALIAS("platform:pxa2xx-spi");
#define TIMOUT_DFLT 1000
-#define DMA_INT_MASK (DCSR_ENDINTR | DCSR_STARTINTR | DCSR_BUSERR)
-#define RESET_DMA_CHANNEL (DCSR_NODESC | DMA_INT_MASK)
-#define IS_DMA_ALIGNED(x) IS_ALIGNED((unsigned long)(x), DMA_ALIGNMENT)
-#define MAX_DMA_LEN 8191
-#define DMA_ALIGNMENT 8
-
/*
* for testing SSCR1 changes that require SSP restart, basically
* everything except the service and interrupt enables, the pxa270 developer
@@ -66,105 +63,97 @@ MODULE_ALIAS("platform:pxa2xx-spi");
| SSCR1_RFT | SSCR1_TFT | SSCR1_MWDS \
| SSCR1_SPH | SSCR1_SPO | SSCR1_LBM)
-#define DEFINE_SSP_REG(reg, off) \
-static inline u32 read_##reg(void const __iomem *p) \
-{ return __raw_readl(p + (off)); } \
-\
-static inline void write_##reg(u32 v, void __iomem *p) \
-{ __raw_writel(v, p + (off)); }
-
-DEFINE_SSP_REG(SSCR0, 0x00)
-DEFINE_SSP_REG(SSCR1, 0x04)
-DEFINE_SSP_REG(SSSR, 0x08)
-DEFINE_SSP_REG(SSITR, 0x0c)
-DEFINE_SSP_REG(SSDR, 0x10)
-DEFINE_SSP_REG(SSTO, 0x28)
-DEFINE_SSP_REG(SSPSP, 0x2c)
-
-#define START_STATE ((void*)0)
-#define RUNNING_STATE ((void*)1)
-#define DONE_STATE ((void*)2)
-#define ERROR_STATE ((void*)-1)
-
-struct driver_data {
- /* Driver model hookup */
- struct platform_device *pdev;
-
- /* SSP Info */
- struct ssp_device *ssp;
+#define LPSS_RX_THRESH_DFLT 64
+#define LPSS_TX_LOTHRESH_DFLT 160
+#define LPSS_TX_HITHRESH_DFLT 224
- /* SPI framework hookup */
- enum pxa_ssp_type ssp_type;
- struct spi_master *master;
+/* Offset from drv_data->lpss_base */
+#define SPI_CS_CONTROL 0x18
+#define SPI_CS_CONTROL_SW_MODE BIT(0)
+#define SPI_CS_CONTROL_CS_HIGH BIT(1)
- /* PXA hookup */
- struct pxa2xx_spi_master *master_info;
-
- /* DMA setup stuff */
- int rx_channel;
- int tx_channel;
- u32 *null_dma_buf;
-
- /* SSP register addresses */
- void __iomem *ioaddr;
- u32 ssdr_physical;
-
- /* SSP masks*/
- u32 dma_cr1;
- u32 int_cr1;
- u32 clear_sr;
- u32 mask_sr;
-
- /* Maximun clock rate */
- unsigned long max_clk_rate;
-
- /* Message Transfer pump */
- struct tasklet_struct pump_transfers;
-
- /* Current message transfer state info */
- struct spi_message* cur_msg;
- struct spi_transfer* cur_transfer;
- struct chip_data *cur_chip;
- size_t len;
- void *tx;
- void *tx_end;
- void *rx;
- void *rx_end;
- int dma_mapped;
- dma_addr_t rx_dma;
- dma_addr_t tx_dma;
- size_t rx_map_len;
- size_t tx_map_len;
- u8 n_bytes;
- u32 dma_width;
- int (*write)(struct driver_data *drv_data);
- int (*read)(struct driver_data *drv_data);
- irqreturn_t (*transfer_handler)(struct driver_data *drv_data);
- void (*cs_control)(u32 command);
-};
+static bool is_lpss_ssp(const struct driver_data *drv_data)
+{
+ return drv_data->ssp_type == LPSS_SSP;
+}
-struct chip_data {
- u32 cr0;
- u32 cr1;
- u32 psp;
- u32 timeout;
- u8 n_bytes;
- u32 dma_width;
- u32 dma_burst_size;
- u32 threshold;
- u32 dma_threshold;
- u8 enable_dma;
- u8 bits_per_word;
- u32 speed_hz;
- union {
- int gpio_cs;
- unsigned int frm;
- };
- int gpio_cs_inverted;
- int (*write)(struct driver_data *drv_data);
- int (*read)(struct driver_data *drv_data);
- void (*cs_control)(u32 command);
-};
+/*
+ * Read and write LPSS SSP private registers. Caller must first check that
+ * is_lpss_ssp() returns true before these can be called.
+ */
+static u32 __lpss_ssp_read_priv(struct driver_data *drv_data, unsigned offset)
+{
+ WARN_ON(!drv_data->lpss_base);
+ return readl(drv_data->lpss_base + offset);
+}
+
+static void __lpss_ssp_write_priv(struct driver_data *drv_data,
+ unsigned offset, u32 value)
+{
+ WARN_ON(!drv_data->lpss_base);
+ writel(value, drv_data->lpss_base + offset);
+}
+
+/*
+ * lpss_ssp_setup - perform LPSS SSP specific setup
+ * @drv_data: pointer to the driver private data
+ *
+ * Perform LPSS SSP specific setup. This function must be called first if
+ * one is going to use LPSS SSP private registers.
+ */
+static void lpss_ssp_setup(struct driver_data *drv_data)
+{
+ unsigned offset = 0x400;
+ u32 value, orig;
+
+ if (!is_lpss_ssp(drv_data))
+ return;
+
+ /*
+ * Perform auto-detection of the LPSS SSP private registers. They
+ * can be either at 1k or 2k offset from the base address.
+ */
+ orig = readl(drv_data->ioaddr + offset + SPI_CS_CONTROL);
+
+ value = orig | SPI_CS_CONTROL_SW_MODE;
+ writel(value, drv_data->ioaddr + offset + SPI_CS_CONTROL);
+ value = readl(drv_data->ioaddr + offset + SPI_CS_CONTROL);
+ if (value != (orig | SPI_CS_CONTROL_SW_MODE)) {
+ offset = 0x800;
+ goto detection_done;
+ }
+
+ value &= ~SPI_CS_CONTROL_SW_MODE;
+ writel(value, drv_data->ioaddr + offset + SPI_CS_CONTROL);
+ value = readl(drv_data->ioaddr + offset + SPI_CS_CONTROL);
+ if (value != orig) {
+ offset = 0x800;
+ goto detection_done;
+ }
+
+detection_done:
+ /* Now set the LPSS base */
+ drv_data->lpss_base = drv_data->ioaddr + offset;
+
+ /* Enable software chip select control */
+ value = SPI_CS_CONTROL_SW_MODE | SPI_CS_CONTROL_CS_HIGH;
+ __lpss_ssp_write_priv(drv_data, SPI_CS_CONTROL, value);
+}
+
+static void lpss_ssp_cs_control(struct driver_data *drv_data, bool enable)
+{
+ u32 value;
+
+ if (!is_lpss_ssp(drv_data))
+ return;
+
+ value = __lpss_ssp_read_priv(drv_data, SPI_CS_CONTROL);
+ if (enable)
+ value &= ~SPI_CS_CONTROL_CS_HIGH;
+ else
+ value |= SPI_CS_CONTROL_CS_HIGH;
+ __lpss_ssp_write_priv(drv_data, SPI_CS_CONTROL, value);
+}
static void cs_assert(struct driver_data *drv_data)
{
@@ -180,8 +169,12 @@ static void cs_assert(struct driver_data *drv_data)
return;
}
- if (gpio_is_valid(chip->gpio_cs))
+ if (gpio_is_valid(chip->gpio_cs)) {
gpio_set_value(chip->gpio_cs, chip->gpio_cs_inverted);
+ return;
+ }
+
+ lpss_ssp_cs_control(drv_data, true);
}
static void cs_deassert(struct driver_data *drv_data)
@@ -196,30 +189,15 @@ static void cs_deassert(struct driver_data *drv_data)
return;
}
- if (gpio_is_valid(chip->gpio_cs))
+ if (gpio_is_valid(chip->gpio_cs)) {
gpio_set_value(chip->gpio_cs, !chip->gpio_cs_inverted);
-}
-
-static void write_SSSR_CS(struct driver_data *drv_data, u32 val)
-{
- void __iomem *reg = drv_data->ioaddr;
-
- if (drv_data->ssp_type == CE4100_SSP)
- val |= read_SSSR(reg) & SSSR_ALT_FRM_MASK;
-
- write_SSSR(val, reg);
-}
+ return;
+ }
-static int pxa25x_ssp_comp(struct driver_data *drv_data)
-{
- if (drv_data->ssp_type == PXA25x_SSP)
- return 1;
- if (drv_data->ssp_type == CE4100_SSP)
- return 1;
- return 0;
+ lpss_ssp_cs_control(drv_data, false);
}
-static int flush(struct driver_data *drv_data)
+int pxa2xx_spi_flush(struct driver_data *drv_data)
{
unsigned long limit = loops_per_jiffy << 1;
@@ -345,7 +323,7 @@ static int u32_reader(struct driver_data *drv_data)
return drv_data->rx == drv_data->rx_end;
}
-static void *next_transfer(struct driver_data *drv_data)
+void *pxa2xx_spi_next_transfer(struct driver_data *drv_data)
{
struct spi_message *msg = drv_data->cur_msg;
struct spi_transfer *trans = drv_data->cur_transfer;
@@ -361,76 +339,6 @@ static void *next_transfer(struct driver_data *drv_data)
return DONE_STATE;
}
-static int map_dma_buffers(struct driver_data *drv_data)
-{
- struct spi_message *msg = drv_data->cur_msg;
- struct device *dev = &msg->spi->dev;
-
- if (!drv_data->cur_chip->enable_dma)
- return 0;
-
- if (msg->is_dma_mapped)
- return drv_data->rx_dma && drv_data->tx_dma;
-
- if (!IS_DMA_ALIGNED(drv_data->rx) || !IS_DMA_ALIGNED(drv_data->tx))
- return 0;
-
- /* Modify setup if rx buffer is null */
- if (drv_data->rx == NULL) {
- *drv_data->null_dma_buf = 0;
- drv_data->rx = drv_data->null_dma_buf;
- drv_data->rx_map_len = 4;
- } else
- drv_data->rx_map_len = drv_data->len;
-
-
- /* Modify setup if tx buffer is null */
- if (drv_data->tx == NULL) {
- *drv_data->null_dma_buf = 0;
- drv_data->tx = drv_data->null_dma_buf;
- drv_data->tx_map_len = 4;
- } else
- drv_data->tx_map_len = drv_data->len;
-
- /* Stream map the tx buffer. Always do DMA_TO_DEVICE first
- * so we flush the cache *before* invalidating it, in case
- * the tx and rx buffers overlap.
- */
- drv_data->tx_dma = dma_map_single(dev, drv_data->tx,
- drv_data->tx_map_len, DMA_TO_DEVICE);
- if (dma_mapping_error(dev, drv_data->tx_dma))
- return 0;
-
- /* Stream map the rx buffer */
- drv_data->rx_dma = dma_map_single(dev, drv_data->rx,
- drv_data->rx_map_len, DMA_FROM_DEVICE);
- if (dma_mapping_error(dev, drv_data->rx_dma)) {
- dma_unmap_single(dev, drv_data->tx_dma,
- drv_data->tx_map_len, DMA_TO_DEVICE);
- return 0;
- }
-
- return 1;
-}
-
-static void unmap_dma_buffers(struct driver_data *drv_data)
-{
- struct device *dev;
-
- if (!drv_data->dma_mapped)
- return;
-
- if (!drv_data->cur_msg->is_dma_mapped) {
- dev = &drv_data->cur_msg->spi->dev;
- dma_unmap_single(dev, drv_data->rx_dma,
- drv_data->rx_map_len, DMA_FROM_DEVICE);
- dma_unmap_single(dev, drv_data->tx_dma,
- drv_data->tx_map_len, DMA_TO_DEVICE);
- }
-
- drv_data->dma_mapped = 0;
-}
-
/* caller already set message->status; dma and pio irqs are blocked */
static void giveback(struct driver_data *drv_data)
{
@@ -483,161 +391,6 @@ static void giveback(struct driver_data *drv_data)
drv_data->cur_chip = NULL;
}
-static int wait_ssp_rx_stall(void const __iomem *ioaddr)
-{
- unsigned long limit = loops_per_jiffy << 1;
-
- while ((read_SSSR(ioaddr) & SSSR_BSY) && --limit)
- cpu_relax();
-
- return limit;
-}
-
-static int wait_dma_channel_stop(int channel)
-{
- unsigned long limit = loops_per_jiffy << 1;
-
- while (!(DCSR(channel) & DCSR_STOPSTATE) && --limit)
- cpu_relax();
-
- return limit;
-}
-
-static void dma_error_stop(struct driver_data *drv_data, const char *msg)
-{
- void __iomem *reg = drv_data->ioaddr;
-
- /* Stop and reset */
- DCSR(drv_data->rx_channel) = RESET_DMA_CHANNEL;
- DCSR(drv_data->tx_channel) = RESET_DMA_CHANNEL;
- write_SSSR_CS(drv_data, drv_data->clear_sr);
- write_SSCR1(read_SSCR1(reg) & ~drv_data->dma_cr1, reg);
- if (!pxa25x_ssp_comp(drv_data))
- write_SSTO(0, reg);
- flush(drv_data);
- write_SSCR0(read_SSCR0(reg) & ~SSCR0_SSE, reg);
-
- unmap_dma_buffers(drv_data);
-
- dev_err(&drv_data->pdev->dev, "%s\n", msg);
-
- drv_data->cur_msg->state = ERROR_STATE;
- tasklet_schedule(&drv_data->pump_transfers);
-}
-
-static void dma_transfer_complete(struct driver_data *drv_data)
-{
- void __iomem *reg = drv_data->ioaddr;
- struct spi_message *msg = drv_data->cur_msg;
-
- /* Clear and disable interrupts on SSP and DMA channels*/
- write_SSCR1(read_SSCR1(reg) & ~drv_data->dma_cr1, reg);
- write_SSSR_CS(drv_data, drv_data->clear_sr);
- DCSR(drv_data->tx_channel) = RESET_DMA_CHANNEL;
- DCSR(drv_data->rx_channel) = RESET_DMA_CHANNEL;
-
- if (wait_dma_channel_stop(drv_data->rx_channel) == 0)
- dev_err(&drv_data->pdev->dev,
- "dma_handler: dma rx channel stop failed\n");
-
- if (wait_ssp_rx_stall(drv_data->ioaddr) == 0)
- dev_err(&drv_data->pdev->dev,
- "dma_transfer: ssp rx stall failed\n");
-
- unmap_dma_buffers(drv_data);
-
- /* update the buffer pointer for the amount completed in dma */
- drv_data->rx += drv_data->len -
- (DCMD(drv_data->rx_channel) & DCMD_LENGTH);
-
- /* read trailing data from fifo, it does not matter how many
- * bytes are in the fifo just read until buffer is full
- * or fifo is empty, which ever occurs first */
- drv_data->read(drv_data);
-
- /* return count of what was actually read */
- msg->actual_length += drv_data->len -
- (drv_data->rx_end - drv_data->rx);
-
- /* Transfer delays and chip select release are
- * handled in pump_transfers or giveback
- */
-
- /* Move to next transfer */
- msg->state = next_transfer(drv_data);
-
- /* Schedule transfer tasklet */
- tasklet_schedule(&drv_data->pump_transfers);
-}
-
-static void dma_handler(int channel, void *data)
-{
- struct driver_data *drv_data = data;
- u32 irq_status = DCSR(channel) & DMA_INT_MASK;
-
- if (irq_status & DCSR_BUSERR) {
-
- if (channel == drv_data->tx_channel)
- dma_error_stop(drv_data,
- "dma_handler: "
- "bad bus address on tx channel");
- else
- dma_error_stop(drv_data,
- "dma_handler: "
- "bad bus address on rx channel");
- return;
- }
-
- /* PXA255x_SSP has no timeout interrupt, wait for tailing bytes */
- if ((channel == drv_data->tx_channel)
- && (irq_status & DCSR_ENDINTR)
- && (drv_data->ssp_type == PXA25x_SSP)) {
-
- /* Wait for rx to stall */
- if (wait_ssp_rx_stall(drv_data->ioaddr) == 0)
- dev_err(&drv_data->pdev->dev,
- "dma_handler: ssp rx stall failed\n");
-
- /* finish this transfer, start the next */
- dma_transfer_complete(drv_data);
- }
-}
-
-static irqreturn_t dma_transfer(struct driver_data *drv_data)
-{
- u32 irq_status;
- void __iomem *reg = drv_data->ioaddr;
-
- irq_status = read_SSSR(reg) & drv_data->mask_sr;
- if (irq_status & SSSR_ROR) {
- dma_error_stop(drv_data, "dma_transfer: fifo overrun");
- return IRQ_HANDLED;
- }
-
- /* Check for false positive timeout */
- if ((irq_status & SSSR_TINT)
- && (DCSR(drv_data->tx_channel) & DCSR_RUN)) {
- write_SSSR(SSSR_TINT, reg);
- return IRQ_HANDLED;
- }
-
- if (irq_status & SSSR_TINT || drv_data->rx == drv_data->rx_end) {
-
- /* Clear and disable timeout interrupt, do the rest in
- * dma_transfer_complete */
- if (!pxa25x_ssp_comp(drv_data))
- write_SSTO(0, reg);
-
- /* finish this transfer, start the next */
- dma_transfer_complete(drv_data);
-
- return IRQ_HANDLED;
- }
-
- /* Opps problem detected */
- return IRQ_NONE;
-}
-
static void reset_sccr1(struct driver_data *drv_data)
{
void __iomem *reg = drv_data->ioaddr;
@@ -659,7 +412,7 @@ static void int_error_stop(struct driver_data *drv_data, const char* msg)
reset_sccr1(drv_data);
if (!pxa25x_ssp_comp(drv_data))
write_SSTO(0, reg);
- flush(drv_data);
+ pxa2xx_spi_flush(drv_data);
write_SSCR0(read_SSCR0(reg) & ~SSCR0_SSE, reg);
dev_err(&drv_data->pdev->dev, "%s\n", msg);
@@ -687,7 +440,7 @@ static void int_transfer_complete(struct driver_data *drv_data)
*/
/* Move to next transfer */
- drv_data->cur_msg->state = next_transfer(drv_data);
+ drv_data->cur_msg->state = pxa2xx_spi_next_transfer(drv_data);
/* Schedule transfer tasklet */
tasklet_schedule(&drv_data->pump_transfers);
@@ -767,10 +520,20 @@ static irqreturn_t ssp_int(int irq, void *dev_id)
{
struct driver_data *drv_data = dev_id;
void __iomem *reg = drv_data->ioaddr;
- u32 sccr1_reg = read_SSCR1(reg);
+ u32 sccr1_reg;
u32 mask = drv_data->mask_sr;
u32 status;
+ /*
+ * The IRQ might be shared with other peripherals so we must first
+ * check that are we RPM suspended or not. If we are we assume that
+ * the IRQ was not for us (we shouldn't be RPM suspended when the
+ * interrupt is enabled).
+ */
+ if (pm_runtime_suspended(&drv_data->pdev->dev))
+ return IRQ_NONE;
+
+ sccr1_reg = read_SSCR1(reg);
status = read_SSSR(reg);
/* Ignore possible writes if we don't need to write */
@@ -798,103 +561,6 @@ static irqreturn_t ssp_int(int irq, void *dev_id)
return drv_data->transfer_handler(drv_data);
}
-static int set_dma_burst_and_threshold(struct chip_data *chip,
- struct spi_device *spi,
- u8 bits_per_word, u32 *burst_code,
- u32 *threshold)
-{
- struct pxa2xx_spi_chip *chip_info =
- (struct pxa2xx_spi_chip *)spi->controller_data;
- int bytes_per_word;
- int burst_bytes;
- int thresh_words;
- int req_burst_size;
- int retval = 0;
-
- /* Set the threshold (in registers) to equal the same amount of data
- * as represented by burst size (in bytes). The computation below
- * is (burst_size rounded up to nearest 8 byte, word or long word)
- * divided by (bytes/register); the tx threshold is the inverse of
- * the rx, so that there will always be enough data in the rx fifo
- * to satisfy a burst, and there will always be enough space in the
- * tx fifo to accept a burst (a tx burst will overwrite the fifo if
- * there is not enough space), there must always remain enough empty
- * space in the rx fifo for any data loaded to the tx fifo.
- * Whenever burst_size (in bytes) equals bits/word, the fifo threshold
- * will be 8, or half the fifo;
- * The threshold can only be set to 2, 4 or 8, but not 16, because
- * to burst 16 to the tx fifo, the fifo would have to be empty;
- * however, the minimum fifo trigger level is 1, and the tx will
- * request service when the fifo is at this level, with only 15 spaces.
- */
-
- /* find bytes/word */
- if (bits_per_word <= 8)
- bytes_per_word = 1;
- else if (bits_per_word <= 16)
- bytes_per_word = 2;
- else
- bytes_per_word = 4;
-
- /* use struct pxa2xx_spi_chip->dma_burst_size if available */
- if (chip_info)
- req_burst_size = chip_info->dma_burst_size;
- else {
- switch (chip->dma_burst_size) {
- default:
- /* if the default burst size is not set,
- * do it now */
- chip->dma_burst_size = DCMD_BURST8;
- case DCMD_BURST8:
- req_burst_size = 8;
- break;
- case DCMD_BURST16:
- req_burst_size = 16;
- break;
- case DCMD_BURST32:
- req_burst_size = 32;
- break;
- }
- }
- if (req_burst_size <= 8) {
- *burst_code = DCMD_BURST8;
- burst_bytes = 8;
- } else if (req_burst_size <= 16) {
- if (bytes_per_word == 1) {
- /* don't burst more than 1/2 the fifo */
- *burst_code = DCMD_BURST8;
- burst_bytes = 8;
- retval = 1;
- } else {
- *burst_code = DCMD_BURST16;
- burst_bytes = 16;
- }
- } else {
- if (bytes_per_word == 1) {
- /* don't burst more than 1/2 the fifo */
- *burst_code = DCMD_BURST8;
- burst_bytes = 8;
- retval = 1;
- } else if (bytes_per_word == 2) {
- /* don't burst more than 1/2 the fifo */
- *burst_code = DCMD_BURST16;
- burst_bytes = 16;
- retval = 1;
- } else {
- *burst_code = DCMD_BURST32;
- burst_bytes = 32;
- }
- }
-
- thresh_words = burst_bytes / bytes_per_word;
-
- /* thresh_words will be between 2 and 8 */
- *threshold = (SSCR1_RxTresh(thresh_words) & SSCR1_RFT)
- | (SSCR1_TxTresh(16-thresh_words) & SSCR1_TFT);
-
- return retval;
-}
-
static unsigned int ssp_get_clk_div(struct driver_data *drv_data, int rate)
{
unsigned long ssp_clk = drv_data->max_clk_rate;
@@ -956,8 +622,8 @@ static void pump_transfers(unsigned long data)
cs_deassert(drv_data);
}
- /* Check for transfers that need multiple DMA segments */
- if (transfer->len > MAX_DMA_LEN && chip->enable_dma) {
+ /* Check if we can DMA this transfer */
+ if (!pxa2xx_spi_dma_is_possible(transfer->len) && chip->enable_dma) {
/* reject already-mapped transfers; PIO won't always work */
if (message->is_dma_mapped
@@ -980,21 +646,20 @@ static void pump_transfers(unsigned long data)
}
/* Setup the transfer state based on the type of transfer */
- if (flush(drv_data) == 0) {
+ if (pxa2xx_spi_flush(drv_data) == 0) {
dev_err(&drv_data->pdev->dev, "pump_transfers: flush failed\n");
message->status = -EIO;
giveback(drv_data);
return;
}
drv_data->n_bytes = chip->n_bytes;
- drv_data->dma_width = chip->dma_width;
drv_data->tx = (void *)transfer->tx_buf;
drv_data->tx_end = drv_data->tx + transfer->len;
drv_data->rx = transfer->rx_buf;
drv_data->rx_end = drv_data->rx + transfer->len;
drv_data->rx_dma = transfer->rx_dma;
drv_data->tx_dma = transfer->tx_dma;
- drv_data->len = transfer->len & DCMD_LENGTH;
+ drv_data->len = transfer->len;
drv_data->write = drv_data->tx ? chip->write : null_writer;
drv_data->read = drv_data->rx ? chip->read : null_reader;
@@ -1015,21 +680,18 @@ static void pump_transfers(unsigned long data)
if (bits <= 8) {
drv_data->n_bytes = 1;
- drv_data->dma_width = DCMD_WIDTH1;
drv_data->read = drv_data->read != null_reader ?
u8_reader : null_reader;
drv_data->write = drv_data->write != null_writer ?
u8_writer : null_writer;
} else if (bits <= 16) {
drv_data->n_bytes = 2;
- drv_data->dma_width = DCMD_WIDTH2;
drv_data->read = drv_data->read != null_reader ?
u16_reader : null_reader;
drv_data->write = drv_data->write != null_writer ?
u16_writer : null_writer;
} else if (bits <= 32) {
drv_data->n_bytes = 4;
- drv_data->dma_width = DCMD_WIDTH4;
drv_data->read = drv_data->read != null_reader ?
u32_reader : null_reader;
drv_data->write = drv_data->write != null_writer ?
@@ -1038,7 +700,8 @@ static void pump_transfers(unsigned long data)
/* if bits/word is changed in dma mode, then must check the
* thresholds and burst also */
if (chip->enable_dma) {
- if (set_dma_burst_and_threshold(chip, message->spi,
+ if (pxa2xx_spi_set_dma_burst_and_threshold(chip,
+ message->spi,
bits, &dma_burst,
&dma_thresh))
if (printk_ratelimit())
@@ -1057,70 +720,21 @@ static void pump_transfers(unsigned long data)
message->state = RUNNING_STATE;
- /* Try to map dma buffer and do a dma transfer if successful, but
- * only if the length is non-zero and less than MAX_DMA_LEN.
- *
- * Zero-length non-descriptor DMA is illegal on PXA2xx; force use
- * of PIO instead. Care is needed above because the transfer may
- * have have been passed with buffers that are already dma mapped.
- * A zero-length transfer in PIO mode will not try to write/read
- * to/from the buffers
- *
- * REVISIT large transfers are exactly where we most want to be
- * using DMA. If this happens much, split those transfers into
- * multiple DMA segments rather than forcing PIO.
- */
drv_data->dma_mapped = 0;
- if (drv_data->len > 0 && drv_data->len <= MAX_DMA_LEN)
- drv_data->dma_mapped = map_dma_buffers(drv_data);
+ if (pxa2xx_spi_dma_is_possible(drv_data->len))
+ drv_data->dma_mapped = pxa2xx_spi_map_dma_buffers(drv_data);
if (drv_data->dma_mapped) {
/* Ensure we have the correct interrupt handler */
- drv_data->transfer_handler = dma_transfer;
-
- /* Setup rx DMA Channel */
- DCSR(drv_data->rx_channel) = RESET_DMA_CHANNEL;
- DSADR(drv_data->rx_channel) = drv_data->ssdr_physical;
- DTADR(drv_data->rx_channel) = drv_data->rx_dma;
- if (drv_data->rx == drv_data->null_dma_buf)
- /* No target address increment */
- DCMD(drv_data->rx_channel) = DCMD_FLOWSRC
- | drv_data->dma_width
- | dma_burst
- | drv_data->len;
- else
- DCMD(drv_data->rx_channel) = DCMD_INCTRGADDR
- | DCMD_FLOWSRC
- | drv_data->dma_width
- | dma_burst
- | drv_data->len;
-
- /* Setup tx DMA Channel */
- DCSR(drv_data->tx_channel) = RESET_DMA_CHANNEL;
- DSADR(drv_data->tx_channel) = drv_data->tx_dma;
- DTADR(drv_data->tx_channel) = drv_data->ssdr_physical;
- if (drv_data->tx == drv_data->null_dma_buf)
- /* No source address increment */
- DCMD(drv_data->tx_channel) = DCMD_FLOWTRG
- | drv_data->dma_width
- | dma_burst
- | drv_data->len;
- else
- DCMD(drv_data->tx_channel) = DCMD_INCSRCADDR
- | DCMD_FLOWTRG
- | drv_data->dma_width
- | dma_burst
- | drv_data->len;
-
- /* Enable dma end irqs on SSP to detect end of transfer */
- if (drv_data->ssp_type == PXA25x_SSP)
- DCMD(drv_data->tx_channel) |= DCMD_ENDIRQEN;
+ drv_data->transfer_handler = pxa2xx_spi_dma_transfer;
+
+ pxa2xx_spi_dma_prepare(drv_data, dma_burst);
/* Clear status and start DMA engine */
cr1 = chip->cr1 | dma_thresh | drv_data->dma_cr1;
write_SSSR(drv_data->clear_sr, reg);
- DCSR(drv_data->rx_channel) |= DCSR_RUN;
- DCSR(drv_data->tx_channel) |= DCSR_RUN;
+
+ pxa2xx_spi_dma_start(drv_data);
} else {
/* Ensure we have the correct interrupt handler */
drv_data->transfer_handler = interrupt_transfer;
@@ -1130,6 +744,13 @@ static void pump_transfers(unsigned long data)
write_SSSR_CS(drv_data, drv_data->clear_sr);
}
+ if (is_lpss_ssp(drv_data)) {
+ if ((read_SSIRF(reg) & 0xff) != chip->lpss_rx_threshold)
+ write_SSIRF(chip->lpss_rx_threshold, reg);
+ if ((read_SSITF(reg) & 0xffff) != chip->lpss_tx_threshold)
+ write_SSITF(chip->lpss_tx_threshold, reg);
+ }
+
/* see if we need to reload the config registers */
if ((read_SSCR0(reg) != cr0)
|| (read_SSCR1(reg) & SSCR1_CHANGE_MASK) !=
@@ -1177,6 +798,27 @@ static int pxa2xx_spi_transfer_one_message(struct spi_master *master,
return 0;
}
+static int pxa2xx_spi_prepare_transfer(struct spi_master *master)
+{
+ struct driver_data *drv_data = spi_master_get_devdata(master);
+
+ pm_runtime_get_sync(&drv_data->pdev->dev);
+ return 0;
+}
+
+static int pxa2xx_spi_unprepare_transfer(struct spi_master *master)
+{
+ struct driver_data *drv_data = spi_master_get_devdata(master);
+
+ /* Disable the SSP now */
+ write_SSCR0(read_SSCR0(drv_data->ioaddr) & ~SSCR0_SSE,
+ drv_data->ioaddr);
+
+ pm_runtime_mark_last_busy(&drv_data->pdev->dev);
+ pm_runtime_put_autosuspend(&drv_data->pdev->dev);
+ return 0;
+}
+
static int setup_cs(struct spi_device *spi, struct chip_data *chip,
struct pxa2xx_spi_chip *chip_info)
{
@@ -1221,8 +863,17 @@ static int setup(struct spi_device *spi)
struct chip_data *chip;
struct driver_data *drv_data = spi_master_get_devdata(spi->master);
unsigned int clk_div;
- uint tx_thres = TX_THRESH_DFLT;
- uint rx_thres = RX_THRESH_DFLT;
+ uint tx_thres, tx_hi_thres, rx_thres;
+
+ if (is_lpss_ssp(drv_data)) {
+ tx_thres = LPSS_TX_LOTHRESH_DFLT;
+ tx_hi_thres = LPSS_TX_HITHRESH_DFLT;
+ rx_thres = LPSS_RX_THRESH_DFLT;
+ } else {
+ tx_thres = TX_THRESH_DFLT;
+ tx_hi_thres = 0;
+ rx_thres = RX_THRESH_DFLT;
+ }
if (!pxa25x_ssp_comp(drv_data)
&& (spi->bits_per_word < 4 || spi->bits_per_word > 32)) {
@@ -1262,8 +913,6 @@ static int setup(struct spi_device *spi)
chip->gpio_cs = -1;
chip->enable_dma = 0;
chip->timeout = TIMOUT_DFLT;
- chip->dma_burst_size = drv_data->master_info->enable_dma ?
- DCMD_BURST8 : 0;
}
/* protocol drivers may change the chip settings, so...
@@ -1277,23 +926,37 @@ static int setup(struct spi_device *spi)
chip->timeout = chip_info->timeout;
if (chip_info->tx_threshold)
tx_thres = chip_info->tx_threshold;
+ if (chip_info->tx_hi_threshold)
+ tx_hi_thres = chip_info->tx_hi_threshold;
if (chip_info->rx_threshold)
rx_thres = chip_info->rx_threshold;
chip->enable_dma = drv_data->master_info->enable_dma;
chip->dma_threshold = 0;
if (chip_info->enable_loopback)
chip->cr1 = SSCR1_LBM;
+ } else if (ACPI_HANDLE(&spi->dev)) {
+ /*
+ * Slave devices enumerated from ACPI namespace don't
+ * usually have chip_info but we still might want to use
+ * DMA with them.
+ */
+ chip->enable_dma = drv_data->master_info->enable_dma;
}
chip->threshold = (SSCR1_RxTresh(rx_thres) & SSCR1_RFT) |
(SSCR1_TxTresh(tx_thres) & SSCR1_TFT);
+ chip->lpss_rx_threshold = SSIRF_RxThresh(rx_thres);
+ chip->lpss_tx_threshold = SSITF_TxLoThresh(tx_thres)
+ | SSITF_TxHiThresh(tx_hi_thres);
+
/* set dma burst and threshold outside of chip_info path so that if
* chip_info goes away after setting chip->enable_dma, the
* burst and threshold can still respond to changes in bits_per_word */
if (chip->enable_dma) {
/* set up legal burst and threshold for dma */
- if (set_dma_burst_and_threshold(chip, spi, spi->bits_per_word,
+ if (pxa2xx_spi_set_dma_burst_and_threshold(chip, spi,
+ spi->bits_per_word,
&chip->dma_burst_size,
&chip->dma_threshold)) {
dev_warn(&spi->dev, "in setup: DMA burst size reduced "
@@ -1314,6 +977,9 @@ static int setup(struct spi_device *spi)
chip->cr1 |= (((spi->mode & SPI_CPHA) != 0) ? SSCR1_SPH : 0)
| (((spi->mode & SPI_CPOL) != 0) ? SSCR1_SPO : 0);
+ if (spi->mode & SPI_LOOP)
+ chip->cr1 |= SSCR1_LBM;
+
/* NOTE: PXA25x_SSP _could_ use external clocking ... */
if (!pxa25x_ssp_comp(drv_data))
dev_dbg(&spi->dev, "%ld Hz actual, %s\n",
@@ -1328,18 +994,15 @@ static int setup(struct spi_device *spi)
if (spi->bits_per_word <= 8) {
chip->n_bytes = 1;
- chip->dma_width = DCMD_WIDTH1;
chip->read = u8_reader;
chip->write = u8_writer;
} else if (spi->bits_per_word <= 16) {
chip->n_bytes = 2;
- chip->dma_width = DCMD_WIDTH2;
chip->read = u16_reader;
chip->write = u16_writer;
} else if (spi->bits_per_word <= 32) {
chip->cr0 |= SSCR0_EDSS;
chip->n_bytes = 4;
- chip->dma_width = DCMD_WIDTH4;
chip->read = u32_reader;
chip->write = u32_writer;
} else {
@@ -1370,6 +1033,99 @@ static void cleanup(struct spi_device *spi)
kfree(chip);
}
+#ifdef CONFIG_ACPI
+static int pxa2xx_spi_acpi_add_dma(struct acpi_resource *res, void *data)
+{
+ struct pxa2xx_spi_master *pdata = data;
+
+ if (res->type == ACPI_RESOURCE_TYPE_FIXED_DMA) {
+ const struct acpi_resource_fixed_dma *dma;
+
+ dma = &res->data.fixed_dma;
+ if (pdata->tx_slave_id < 0) {
+ pdata->tx_slave_id = dma->request_lines;
+ pdata->tx_chan_id = dma->channels;
+ } else if (pdata->rx_slave_id < 0) {
+ pdata->rx_slave_id = dma->request_lines;
+ pdata->rx_chan_id = dma->channels;
+ }
+ }
+
+ /* Tell the ACPI core to skip this resource */
+ return 1;
+}
+
+static struct pxa2xx_spi_master *
+pxa2xx_spi_acpi_get_pdata(struct platform_device *pdev)
+{
+ struct pxa2xx_spi_master *pdata;
+ struct list_head resource_list;
+ struct acpi_device *adev;
+ struct ssp_device *ssp;
+ struct resource *res;
+ int devid;
+
+ if (!ACPI_HANDLE(&pdev->dev) ||
+ acpi_bus_get_device(ACPI_HANDLE(&pdev->dev), &adev))
+ return NULL;
+
+ pdata = devm_kzalloc(&pdev->dev, sizeof(*ssp), GFP_KERNEL);
+ if (!pdata) {
+ dev_err(&pdev->dev,
+ "failed to allocate memory for platform data\n");
+ return NULL;
+ }
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return NULL;
+
+ ssp = &pdata->ssp;
+
+ ssp->phys_base = res->start;
+ ssp->mmio_base = devm_request_and_ioremap(&pdev->dev, res);
+ if (!ssp->mmio_base) {
+ dev_err(&pdev->dev, "failed to ioremap mmio_base\n");
+ return NULL;
+ }
+
+ ssp->clk = devm_clk_get(&pdev->dev, NULL);
+ ssp->irq = platform_get_irq(pdev, 0);
+ ssp->type = LPSS_SSP;
+ ssp->pdev = pdev;
+
+ ssp->port_id = -1;
+ if (adev->pnp.unique_id && !kstrtoint(adev->pnp.unique_id, 0, &devid))
+ ssp->port_id = devid;
+
+ pdata->num_chipselect = 1;
+ pdata->rx_slave_id = -1;
+ pdata->tx_slave_id = -1;
+
+ INIT_LIST_HEAD(&resource_list);
+ acpi_dev_get_resources(adev, &resource_list, pxa2xx_spi_acpi_add_dma,
+ pdata);
+ acpi_dev_free_resource_list(&resource_list);
+
+ pdata->enable_dma = pdata->rx_slave_id >= 0 && pdata->tx_slave_id >= 0;
+
+ return pdata;
+}
+
+static struct acpi_device_id pxa2xx_spi_acpi_match[] = {
+ { "INT33C0", 0 },
+ { "INT33C1", 0 },
+ { },
+};
+MODULE_DEVICE_TABLE(acpi, pxa2xx_spi_acpi_match);
+#else
+static inline struct pxa2xx_spi_master *
+pxa2xx_spi_acpi_get_pdata(struct platform_device *pdev)
+{
+ return NULL;
+}
+#endif
+
static int pxa2xx_spi_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
@@ -1381,8 +1137,11 @@ static int pxa2xx_spi_probe(struct platform_device *pdev)
platform_info = dev_get_platdata(dev);
if (!platform_info) {
- dev_err(&pdev->dev, "missing platform data\n");
- return -ENODEV;
+ platform_info = pxa2xx_spi_acpi_get_pdata(pdev);
+ if (!platform_info) {
+ dev_err(&pdev->dev, "missing platform data\n");
+ return -ENODEV;
+ }
}
ssp = pxa_ssp_request(pdev->id, pdev->name);
@@ -1409,8 +1168,9 @@ static int pxa2xx_spi_probe(struct platform_device *pdev)
master->dev.parent = &pdev->dev;
master->dev.of_node = pdev->dev.of_node;
+ ACPI_HANDLE_SET(&master->dev, ACPI_HANDLE(&pdev->dev));
/* the spi->mode bits understood by this driver: */
- master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
+ master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP;
master->bus_num = ssp->port_id;
master->num_chipselect = platform_info->num_chipselect;
@@ -1418,6 +1178,8 @@ static int pxa2xx_spi_probe(struct platform_device *pdev)
master->cleanup = cleanup;
master->setup = setup;
master->transfer_one_message = pxa2xx_spi_transfer_one_message;
+ master->prepare_transfer_hardware = pxa2xx_spi_prepare_transfer;
+ master->unprepare_transfer_hardware = pxa2xx_spi_unprepare_transfer;
drv_data->ssp_type = ssp->type;
drv_data->null_dma_buf = (u32 *)PTR_ALIGN(&drv_data[1], DMA_ALIGNMENT);
@@ -1431,7 +1193,7 @@ static int pxa2xx_spi_probe(struct platform_device *pdev)
drv_data->mask_sr = SSSR_RFS | SSSR_TFS | SSSR_ROR;
} else {
drv_data->int_cr1 = SSCR1_TIE | SSCR1_RIE | SSCR1_TINTE;
- drv_data->dma_cr1 = SSCR1_TSRE | SSCR1_RSRE | SSCR1_TINTE;
+ drv_data->dma_cr1 = DEFAULT_DMA_CR1;
drv_data->clear_sr = SSSR_ROR | SSSR_TINT;
drv_data->mask_sr = SSSR_TINT | SSSR_RFS | SSSR_TFS | SSSR_ROR;
}
@@ -1447,31 +1209,11 @@ static int pxa2xx_spi_probe(struct platform_device *pdev)
drv_data->tx_channel = -1;
drv_data->rx_channel = -1;
if (platform_info->enable_dma) {
-
- /* Get two DMA channels (rx and tx) */
- drv_data->rx_channel = pxa_request_dma("pxa2xx_spi_ssp_rx",
- DMA_PRIO_HIGH,
- dma_handler,
- drv_data);
- if (drv_data->rx_channel < 0) {
- dev_err(dev, "problem (%d) requesting rx channel\n",
- drv_data->rx_channel);
- status = -ENODEV;
- goto out_error_irq_alloc;
- }
- drv_data->tx_channel = pxa_request_dma("pxa2xx_spi_ssp_tx",
- DMA_PRIO_MEDIUM,
- dma_handler,
- drv_data);
- if (drv_data->tx_channel < 0) {
- dev_err(dev, "problem (%d) requesting tx channel\n",
- drv_data->tx_channel);
- status = -ENODEV;
- goto out_error_dma_alloc;
+ status = pxa2xx_spi_dma_setup(drv_data);
+ if (status) {
+ dev_warn(dev, "failed to setup DMA, using PIO\n");
+ platform_info->enable_dma = false;
}
-
- DRCMR(ssp->drcmr_rx) = DRCMR_MAPVLD | drv_data->rx_channel;
- DRCMR(ssp->drcmr_tx) = DRCMR_MAPVLD | drv_data->tx_channel;
}
/* Enable SOC clock */
@@ -1492,6 +1234,8 @@ static int pxa2xx_spi_probe(struct platform_device *pdev)
write_SSTO(0, drv_data->ioaddr);
write_SSPSP(0, drv_data->ioaddr);
+ lpss_ssp_setup(drv_data);
+
tasklet_init(&drv_data->pump_transfers, pump_transfers,
(unsigned long)drv_data);
@@ -1503,18 +1247,16 @@ static int pxa2xx_spi_probe(struct platform_device *pdev)
goto out_error_clock_enabled;
}
+ pm_runtime_set_autosuspend_delay(&pdev->dev, 50);
+ pm_runtime_use_autosuspend(&pdev->dev);
+ pm_runtime_set_active(&pdev->dev);
+ pm_runtime_enable(&pdev->dev);
+
return status;
out_error_clock_enabled:
clk_disable_unprepare(ssp->clk);
-
-out_error_dma_alloc:
- if (drv_data->tx_channel != -1)
- pxa_free_dma(drv_data->tx_channel);
- if (drv_data->rx_channel != -1)
- pxa_free_dma(drv_data->rx_channel);
-
-out_error_irq_alloc:
+ pxa2xx_spi_dma_release(drv_data);
free_irq(ssp->irq, drv_data);
out_error_master_alloc:
@@ -1532,17 +1274,18 @@ static int pxa2xx_spi_remove(struct platform_device *pdev)
return 0;
ssp = drv_data->ssp;
+ pm_runtime_get_sync(&pdev->dev);
+
/* Disable the SSP at the peripheral and SOC level */
write_SSCR0(0, drv_data->ioaddr);
clk_disable_unprepare(ssp->clk);
/* Release DMA */
- if (drv_data->master_info->enable_dma) {
- DRCMR(ssp->drcmr_rx) = 0;
- DRCMR(ssp->drcmr_tx) = 0;
- pxa_free_dma(drv_data->tx_channel);
- pxa_free_dma(drv_data->rx_channel);
- }
+ if (drv_data->master_info->enable_dma)
+ pxa2xx_spi_dma_release(drv_data);
+
+ pm_runtime_put_noidle(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
/* Release IRQ */
free_irq(ssp->irq, drv_data);
@@ -1589,12 +1332,7 @@ static int pxa2xx_spi_resume(struct device *dev)
struct ssp_device *ssp = drv_data->ssp;
int status = 0;
- if (drv_data->rx_channel != -1)
- DRCMR(drv_data->ssp->drcmr_rx) =
- DRCMR_MAPVLD | drv_data->rx_channel;
- if (drv_data->tx_channel != -1)
- DRCMR(drv_data->ssp->drcmr_tx) =
- DRCMR_MAPVLD | drv_data->tx_channel;
+ pxa2xx_spi_dma_resume(drv_data);
/* Enable the SSP clock */
clk_prepare_enable(ssp->clk);
@@ -1608,20 +1346,38 @@ static int pxa2xx_spi_resume(struct device *dev)
return 0;
}
+#endif
+
+#ifdef CONFIG_PM_RUNTIME
+static int pxa2xx_spi_runtime_suspend(struct device *dev)
+{
+ struct driver_data *drv_data = dev_get_drvdata(dev);
+
+ clk_disable_unprepare(drv_data->ssp->clk);
+ return 0;
+}
+
+static int pxa2xx_spi_runtime_resume(struct device *dev)
+{
+ struct driver_data *drv_data = dev_get_drvdata(dev);
+
+ clk_prepare_enable(drv_data->ssp->clk);
+ return 0;
+}
+#endif
static const struct dev_pm_ops pxa2xx_spi_pm_ops = {
- .suspend = pxa2xx_spi_suspend,
- .resume = pxa2xx_spi_resume,
+ SET_SYSTEM_SLEEP_PM_OPS(pxa2xx_spi_suspend, pxa2xx_spi_resume)
+ SET_RUNTIME_PM_OPS(pxa2xx_spi_runtime_suspend,
+ pxa2xx_spi_runtime_resume, NULL)
};
-#endif
static struct platform_driver driver = {
.driver = {
.name = "pxa2xx-spi",
.owner = THIS_MODULE,
-#ifdef CONFIG_PM
.pm = &pxa2xx_spi_pm_ops,
-#endif
+ .acpi_match_table = ACPI_PTR(pxa2xx_spi_acpi_match),
},
.probe = pxa2xx_spi_probe,
.remove = pxa2xx_spi_remove,
diff --git a/drivers/spi/spi-pxa2xx.h b/drivers/spi/spi-pxa2xx.h
new file mode 100644
index 0000000..5adc2a1
--- /dev/null
+++ b/drivers/spi/spi-pxa2xx.h
@@ -0,0 +1,221 @@
+/*
+ * Copyright (C) 2005 Stephen Street / StreetFire Sound Labs
+ * Copyright (C) 2013, Intel Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef SPI_PXA2XX_H
+#define SPI_PXA2XX_H
+
+#include <linux/atomic.h>
+#include <linux/dmaengine.h>
+#include <linux/errno.h>
+#include <linux/io.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/pxa2xx_ssp.h>
+#include <linux/scatterlist.h>
+#include <linux/sizes.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/pxa2xx_spi.h>
+
+struct driver_data {
+ /* Driver model hookup */
+ struct platform_device *pdev;
+
+ /* SSP Info */
+ struct ssp_device *ssp;
+
+ /* SPI framework hookup */
+ enum pxa_ssp_type ssp_type;
+ struct spi_master *master;
+
+ /* PXA hookup */
+ struct pxa2xx_spi_master *master_info;
+
+ /* PXA private DMA setup stuff */
+ int rx_channel;
+ int tx_channel;
+ u32 *null_dma_buf;
+
+ /* SSP register addresses */
+ void __iomem *ioaddr;
+ u32 ssdr_physical;
+
+ /* SSP masks*/
+ u32 dma_cr1;
+ u32 int_cr1;
+ u32 clear_sr;
+ u32 mask_sr;
+
+ /* Maximun clock rate */
+ unsigned long max_clk_rate;
+
+ /* Message Transfer pump */
+ struct tasklet_struct pump_transfers;
+
+ /* DMA engine support */
+ struct dma_chan *rx_chan;
+ struct dma_chan *tx_chan;
+ struct sg_table rx_sgt;
+ struct sg_table tx_sgt;
+ int rx_nents;
+ int tx_nents;
+ void *dummy;
+ atomic_t dma_running;
+
+ /* Current message transfer state info */
+ struct spi_message *cur_msg;
+ struct spi_transfer *cur_transfer;
+ struct chip_data *cur_chip;
+ size_t len;
+ void *tx;
+ void *tx_end;
+ void *rx;
+ void *rx_end;
+ int dma_mapped;
+ dma_addr_t rx_dma;
+ dma_addr_t tx_dma;
+ size_t rx_map_len;
+ size_t tx_map_len;
+ u8 n_bytes;
+ int (*write)(struct driver_data *drv_data);
+ int (*read)(struct driver_data *drv_data);
+ irqreturn_t (*transfer_handler)(struct driver_data *drv_data);
+ void (*cs_control)(u32 command);
+
+ void __iomem *lpss_base;
+};
+
+struct chip_data {
+ u32 cr0;
+ u32 cr1;
+ u32 psp;
+ u32 timeout;
+ u8 n_bytes;
+ u32 dma_burst_size;
+ u32 threshold;
+ u32 dma_threshold;
+ u16 lpss_rx_threshold;
+ u16 lpss_tx_threshold;
+ u8 enable_dma;
+ u8 bits_per_word;
+ u32 speed_hz;
+ union {
+ int gpio_cs;
+ unsigned int frm;
+ };
+ int gpio_cs_inverted;
+ int (*write)(struct driver_data *drv_data);
+ int (*read)(struct driver_data *drv_data);
+ void (*cs_control)(u32 command);
+};
+
+#define DEFINE_SSP_REG(reg, off) \
+static inline u32 read_##reg(void const __iomem *p) \
+{ return __raw_readl(p + (off)); } \
+\
+static inline void write_##reg(u32 v, void __iomem *p) \
+{ __raw_writel(v, p + (off)); }
+
+DEFINE_SSP_REG(SSCR0, 0x00)
+DEFINE_SSP_REG(SSCR1, 0x04)
+DEFINE_SSP_REG(SSSR, 0x08)
+DEFINE_SSP_REG(SSITR, 0x0c)
+DEFINE_SSP_REG(SSDR, 0x10)
+DEFINE_SSP_REG(SSTO, 0x28)
+DEFINE_SSP_REG(SSPSP, 0x2c)
+DEFINE_SSP_REG(SSITF, SSITF)
+DEFINE_SSP_REG(SSIRF, SSIRF)
+
+#define START_STATE ((void *)0)
+#define RUNNING_STATE ((void *)1)
+#define DONE_STATE ((void *)2)
+#define ERROR_STATE ((void *)-1)
+
+#define IS_DMA_ALIGNED(x) IS_ALIGNED((unsigned long)(x), DMA_ALIGNMENT)
+#define DMA_ALIGNMENT 8
+
+static inline int pxa25x_ssp_comp(struct driver_data *drv_data)
+{
+ if (drv_data->ssp_type == PXA25x_SSP)
+ return 1;
+ if (drv_data->ssp_type == CE4100_SSP)
+ return 1;
+ return 0;
+}
+
+static inline void write_SSSR_CS(struct driver_data *drv_data, u32 val)
+{
+ void __iomem *reg = drv_data->ioaddr;
+
+ if (drv_data->ssp_type == CE4100_SSP)
+ val |= read_SSSR(reg) & SSSR_ALT_FRM_MASK;
+
+ write_SSSR(val, reg);
+}
+
+extern int pxa2xx_spi_flush(struct driver_data *drv_data);
+extern void *pxa2xx_spi_next_transfer(struct driver_data *drv_data);
+
+/*
+ * Select the right DMA implementation.
+ */
+#if defined(CONFIG_SPI_PXA2XX_PXADMA)
+#define SPI_PXA2XX_USE_DMA 1
+#define MAX_DMA_LEN 8191
+#define DEFAULT_DMA_CR1 (SSCR1_TSRE | SSCR1_RSRE | SSCR1_TINTE)
+#elif defined(CONFIG_SPI_PXA2XX_DMA)
+#define SPI_PXA2XX_USE_DMA 1
+#define MAX_DMA_LEN SZ_64K
+#define DEFAULT_DMA_CR1 (SSCR1_TSRE | SSCR1_RSRE | SSCR1_TRAIL)
+#else
+#undef SPI_PXA2XX_USE_DMA
+#define MAX_DMA_LEN 0
+#define DEFAULT_DMA_CR1 0
+#endif
+
+#ifdef SPI_PXA2XX_USE_DMA
+extern bool pxa2xx_spi_dma_is_possible(size_t len);
+extern int pxa2xx_spi_map_dma_buffers(struct driver_data *drv_data);
+extern irqreturn_t pxa2xx_spi_dma_transfer(struct driver_data *drv_data);
+extern int pxa2xx_spi_dma_prepare(struct driver_data *drv_data, u32 dma_burst);
+extern void pxa2xx_spi_dma_start(struct driver_data *drv_data);
+extern int pxa2xx_spi_dma_setup(struct driver_data *drv_data);
+extern void pxa2xx_spi_dma_release(struct driver_data *drv_data);
+extern void pxa2xx_spi_dma_resume(struct driver_data *drv_data);
+extern int pxa2xx_spi_set_dma_burst_and_threshold(struct chip_data *chip,
+ struct spi_device *spi,
+ u8 bits_per_word,
+ u32 *burst_code,
+ u32 *threshold);
+#else
+static inline bool pxa2xx_spi_dma_is_possible(size_t len) { return false; }
+static inline int pxa2xx_spi_map_dma_buffers(struct driver_data *drv_data)
+{
+ return 0;
+}
+#define pxa2xx_spi_dma_transfer NULL
+static inline void pxa2xx_spi_dma_prepare(struct driver_data *drv_data,
+ u32 dma_burst) {}
+static inline void pxa2xx_spi_dma_start(struct driver_data *drv_data) {}
+static inline int pxa2xx_spi_dma_setup(struct driver_data *drv_data)
+{
+ return 0;
+}
+static inline void pxa2xx_spi_dma_release(struct driver_data *drv_data) {}
+static inline void pxa2xx_spi_dma_resume(struct driver_data *drv_data) {}
+static inline int pxa2xx_spi_set_dma_burst_and_threshold(struct chip_data *chip,
+ struct spi_device *spi,
+ u8 bits_per_word,
+ u32 *burst_code,
+ u32 *threshold)
+{
+ return -ENODEV;
+}
+#endif
+
+#endif /* SPI_PXA2XX_H */
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