summaryrefslogtreecommitdiff
path: root/drivers/spi/spi-pxa2xx-dma.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/spi/spi-pxa2xx-dma.c')
-rw-r--r--drivers/spi/spi-pxa2xx-dma.c334
1 files changed, 83 insertions, 251 deletions
diff --git a/drivers/spi/spi-pxa2xx-dma.c b/drivers/spi/spi-pxa2xx-dma.c
index 3c0b55125f1e..08cb6e96ac94 100644
--- a/drivers/spi/spi-pxa2xx-dma.c
+++ b/drivers/spi/spi-pxa2xx-dma.c
@@ -1,167 +1,60 @@
+// SPDX-License-Identifier: GPL-2.0-only
/*
* PXA2xx SPI DMA engine support.
*
- * Copyright (C) 2013, Intel Corporation
+ * Copyright (C) 2013, 2021 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/atomic.h>
+#include <linux/dev_printk.h>
#include <linux/dma-mapping.h>
#include <linux/dmaengine.h>
-#include <linux/pxa2xx_ssp.h>
+#include <linux/errno.h>
+#include <linux/irqreturn.h>
#include <linux/scatterlist.h>
-#include <linux/sizes.h>
+#include <linux/string.h>
+#include <linux/types.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_ATOMIC);
- 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;
-}
+struct device;
static void pxa2xx_spi_dma_transfer_complete(struct driver_data *drv_data,
bool error)
{
- struct spi_message *msg = drv_data->cur_msg;
+ struct spi_message *msg = drv_data->controller->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.
+ * 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;
- }
+ if (!error)
+ error = read_SSSR_bits(drv_data, drv_data->mask_sr) & SSSR_ROR;
/* Clear status & disable interrupts */
- write_SSCR1(read_SSCR1(reg) & ~drv_data->dma_cr1, reg);
+ clear_SSCR1_bits(drv_data, drv_data->dma_cr1);
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);
+ pxa2xx_spi_write(drv_data, SSTO, 0);
- msg->actual_length += drv_data->len;
- msg->state = pxa2xx_spi_next_transfer(drv_data);
- } else {
+ if (error) {
/* In case we got an error we disable the SSP now */
- write_SSCR0(read_SSCR0(reg) & ~SSCR0_SSE, reg);
-
- msg->state = ERROR_STATE;
+ pxa_ssp_disable(drv_data->ssp);
+ msg->status = -EIO;
}
- tasklet_schedule(&drv_data->pump_transfers);
+ spi_finalize_current_transfer(drv_data->controller);
}
}
@@ -172,15 +65,14 @@ static void pxa2xx_spi_dma_callback(void *data)
static struct dma_async_tx_descriptor *
pxa2xx_spi_dma_prepare_one(struct driver_data *drv_data,
- enum dma_transfer_direction dir)
+ enum dma_transfer_direction dir,
+ struct spi_transfer *xfer)
{
- 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;
+ int ret;
switch (drv_data->n_bytes) {
case 1:
@@ -198,89 +90,41 @@ pxa2xx_spi_dma_prepare_one(struct driver_data *drv_data,
cfg.direction = dir;
if (dir == DMA_MEM_TO_DEV) {
- cfg.dst_addr = drv_data->ssdr_physical;
+ cfg.dst_addr = drv_data->ssp->phys_base + SSDR;
cfg.dst_addr_width = width;
- cfg.dst_maxburst = chip->dma_burst_size;
- cfg.slave_id = pdata->tx_slave_id;
+ cfg.dst_maxburst = drv_data->controller_info->dma_burst_size;
- sgt = &drv_data->tx_sgt;
- nents = drv_data->tx_nents;
- chan = drv_data->tx_chan;
+ sgt = &xfer->tx_sg;
+ chan = drv_data->controller->dma_tx;
} else {
- cfg.src_addr = drv_data->ssdr_physical;
+ cfg.src_addr = drv_data->ssp->phys_base + SSDR;
cfg.src_addr_width = width;
- cfg.src_maxburst = chip->dma_burst_size;
- cfg.slave_id = pdata->rx_slave_id;
+ cfg.src_maxburst = drv_data->controller_info->dma_burst_size;
- sgt = &drv_data->rx_sgt;
- nents = drv_data->rx_nents;
- chan = drv_data->rx_chan;
+ sgt = &xfer->rx_sg;
+ chan = drv_data->controller->dma_rx;
}
ret = dmaengine_slave_config(chan, &cfg);
if (ret) {
- dev_warn(&drv_data->pdev->dev, "DMA slave config failed\n");
+ dev_warn(drv_data->ssp->dev, "DMA slave config failed\n");
return NULL;
}
- return dmaengine_prep_slave_sg(chan, sgt->sgl, nents, dir,
+ return dmaengine_prep_slave_sg(chan, sgt->sgl, sgt->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;
+ status = read_SSSR_bits(drv_data, drv_data->mask_sr);
if (status & SSSR_ROR) {
- dev_err(&drv_data->pdev->dev, "FIFO overrun\n");
+ dev_err(drv_data->ssp->dev, "FIFO overrun\n");
- dmaengine_terminate_all(drv_data->rx_chan);
- dmaengine_terminate_all(drv_data->tx_chan);
+ dmaengine_terminate_async(drv_data->controller->dma_rx);
+ dmaengine_terminate_async(drv_data->controller->dma_tx);
pxa2xx_spi_dma_transfer_complete(drv_data, true);
return IRQ_HANDLED;
@@ -289,22 +133,24 @@ irqreturn_t pxa2xx_spi_dma_transfer(struct driver_data *drv_data)
return IRQ_NONE;
}
-int pxa2xx_spi_dma_prepare(struct driver_data *drv_data, u32 dma_burst)
+int pxa2xx_spi_dma_prepare(struct driver_data *drv_data,
+ struct spi_transfer *xfer)
{
struct dma_async_tx_descriptor *tx_desc, *rx_desc;
+ int err;
- tx_desc = pxa2xx_spi_dma_prepare_one(drv_data, DMA_MEM_TO_DEV);
+ tx_desc = pxa2xx_spi_dma_prepare_one(drv_data, DMA_MEM_TO_DEV, xfer);
if (!tx_desc) {
- dev_err(&drv_data->pdev->dev,
- "failed to get DMA TX descriptor\n");
- return -EBUSY;
+ dev_err(drv_data->ssp->dev, "failed to get DMA TX descriptor\n");
+ err = -EBUSY;
+ goto err_tx;
}
- rx_desc = pxa2xx_spi_dma_prepare_one(drv_data, DMA_DEV_TO_MEM);
+ rx_desc = pxa2xx_spi_dma_prepare_one(drv_data, DMA_DEV_TO_MEM, xfer);
if (!rx_desc) {
- dev_err(&drv_data->pdev->dev,
- "failed to get DMA RX descriptor\n");
- return -EBUSY;
+ dev_err(drv_data->ssp->dev, "failed to get DMA RX descriptor\n");
+ err = -EBUSY;
+ goto err_rx;
}
/* We are ready when RX completes */
@@ -314,39 +160,48 @@ int pxa2xx_spi_dma_prepare(struct driver_data *drv_data, u32 dma_burst)
dmaengine_submit(rx_desc);
dmaengine_submit(tx_desc);
return 0;
+
+err_rx:
+ dmaengine_terminate_async(drv_data->controller->dma_tx);
+err_tx:
+ return err;
}
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);
+ dma_async_issue_pending(drv_data->controller->dma_rx);
+ dma_async_issue_pending(drv_data->controller->dma_tx);
atomic_set(&drv_data->dma_running, 1);
}
+void pxa2xx_spi_dma_stop(struct driver_data *drv_data)
+{
+ atomic_set(&drv_data->dma_running, 0);
+ dmaengine_terminate_sync(drv_data->controller->dma_rx);
+ dmaengine_terminate_sync(drv_data->controller->dma_tx);
+}
+
int pxa2xx_spi_dma_setup(struct driver_data *drv_data)
{
- struct pxa2xx_spi_master *pdata = drv_data->master_info;
- struct device *dev = &drv_data->pdev->dev;
+ struct pxa2xx_spi_controller *pdata = drv_data->controller_info;
+ struct spi_controller *controller = drv_data->controller;
+ struct device *dev = drv_data->ssp->dev;
dma_cap_mask_t mask;
dma_cap_zero(mask);
dma_cap_set(DMA_SLAVE, mask);
- drv_data->dummy = devm_kzalloc(dev, SZ_2K, GFP_KERNEL);
- if (!drv_data->dummy)
- return -ENOMEM;
-
- drv_data->tx_chan = dma_request_slave_channel_compat(mask,
- pxa2xx_spi_dma_filter, pdata, dev, "tx");
- if (!drv_data->tx_chan)
+ controller->dma_tx = dma_request_slave_channel_compat(mask,
+ pdata->dma_filter, pdata->tx_param, dev, "tx");
+ if (!controller->dma_tx)
return -ENODEV;
- drv_data->rx_chan = dma_request_slave_channel_compat(mask,
- pxa2xx_spi_dma_filter, pdata, dev, "rx");
- if (!drv_data->rx_chan) {
- dma_release_channel(drv_data->tx_chan);
- drv_data->tx_chan = NULL;
+ controller->dma_rx = dma_request_slave_channel_compat(mask,
+ pdata->dma_filter, pdata->rx_param, dev, "rx");
+ if (!controller->dma_rx) {
+ dma_release_channel(controller->dma_tx);
+ controller->dma_tx = NULL;
return -ENODEV;
}
@@ -355,39 +210,16 @@ int pxa2xx_spi_dma_setup(struct driver_data *drv_data)
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;
+ struct spi_controller *controller = drv_data->controller;
+
+ if (controller->dma_rx) {
+ dmaengine_terminate_sync(controller->dma_rx);
+ dma_release_channel(controller->dma_rx);
+ controller->dma_rx = 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;
+ if (controller->dma_tx) {
+ dmaengine_terminate_sync(controller->dma_tx);
+ dma_release_channel(controller->dma_tx);
+ controller->dma_tx = 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;
-}