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spi: ep93xx: add DT support for Cirrus EP93xx

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- add OF ID match table
- add device tree DMA request, so we can probe defer, in case DMA is not
  ready yet
- drop DMA platform code

Signed-off-by: Nikita Shubin <nikita.shubin@maquefel.me>
Tested-by: Alexander Sverdlin <alexander.sverdlin@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Acked-by: Alexander Sverdlin <alexander.sverdlin@gmail.com>
Acked-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
This commit is contained in:
Nikita Shubin 2024-09-09 11:10:40 +03:00 committed by Arnd Bergmann
parent cb0291776f
commit e79e7c2df6
1 changed files with 23 additions and 43 deletions
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66
drivers/spi/spi-ep93xx.c
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@ -18,18 +18,18 @@
#include <linux/err.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/dma-direction.h>
#include <linux/dma-mapping.h>
#include <linux/dmaengine.h>
#include <linux/bitops.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/property.h>
#include <linux/platform_device.h>
#include <linux/sched.h>
#include <linux/scatterlist.h>
#include <linux/spi/spi.h>
#include <linux/platform_data/dma-ep93xx.h>
#include <linux/platform_data/spi-ep93xx.h>
#define SSPCR0 0x0000
#define SSPCR0_SPO BIT(6)
#define SSPCR0_SPH BIT(7)
@ -92,8 +92,6 @@ struct ep93xx_spi {
size_t fifo_level;
struct dma_chan *dma_rx;
struct dma_chan *dma_tx;
struct ep93xx_dma_data dma_rx_data;
struct ep93xx_dma_data dma_tx_data;
struct sg_table rx_sgt;
struct sg_table tx_sgt;
void *zeropage;
@ -575,46 +573,23 @@ static int ep93xx_spi_unprepare_hardware(struct spi_controller *host)
return 0;
}
static bool ep93xx_spi_dma_filter(struct dma_chan *chan, void *filter_param)
static int ep93xx_spi_setup_dma(struct device *dev, struct ep93xx_spi *espi)
{
if (ep93xx_dma_chan_is_m2p(chan))
return false;
chan->private = filter_param;
return true;
}
static int ep93xx_spi_setup_dma(struct ep93xx_spi *espi)
{
dma_cap_mask_t mask;
int ret;
espi->zeropage = (void *)get_zeroed_page(GFP_KERNEL);
if (!espi->zeropage)
return -ENOMEM;
dma_cap_zero(mask);
dma_cap_set(DMA_SLAVE, mask);
espi->dma_rx_data.port = EP93XX_DMA_SSP;
espi->dma_rx_data.direction = DMA_DEV_TO_MEM;
espi->dma_rx_data.name = "ep93xx-spi-rx";
espi->dma_rx = dma_request_channel(mask, ep93xx_spi_dma_filter,
&espi->dma_rx_data);
if (!espi->dma_rx) {
ret = -ENODEV;
espi->dma_rx = dma_request_chan(dev, "rx");
if (IS_ERR(espi->dma_rx)) {
ret = dev_err_probe(dev, PTR_ERR(espi->dma_rx), "rx DMA setup failed");
goto fail_free_page;
}
espi->dma_tx_data.port = EP93XX_DMA_SSP;
espi->dma_tx_data.direction = DMA_MEM_TO_DEV;
espi->dma_tx_data.name = "ep93xx-spi-tx";
espi->dma_tx = dma_request_channel(mask, ep93xx_spi_dma_filter,
&espi->dma_tx_data);
if (!espi->dma_tx) {
ret = -ENODEV;
espi->dma_tx = dma_request_chan(dev, "tx");
if (IS_ERR(espi->dma_tx)) {
ret = dev_err_probe(dev, PTR_ERR(espi->dma_tx), "tx DMA setup failed");
goto fail_release_rx;
}
@ -647,18 +622,11 @@ static void ep93xx_spi_release_dma(struct ep93xx_spi *espi)
static int ep93xx_spi_probe(struct platform_device *pdev)
{
struct spi_controller *host;
struct ep93xx_spi_info *info;
struct ep93xx_spi *espi;
struct resource *res;
int irq;
int error;
info = dev_get_platdata(&pdev->dev);
if (!info) {
dev_err(&pdev->dev, "missing platform data\n");
return -EINVAL;
}
irq = platform_get_irq(pdev, 0);
if (irq < 0)
return irq;
@ -713,12 +681,17 @@ static int ep93xx_spi_probe(struct platform_device *pdev)
goto fail_release_host;
}
if (info->use_dma && ep93xx_spi_setup_dma(espi))
error = ep93xx_spi_setup_dma(&pdev->dev, espi);
if (error == -EPROBE_DEFER)
goto fail_release_host;
if (error)
dev_warn(&pdev->dev, "DMA setup failed. Falling back to PIO\n");
/* make sure that the hardware is disabled */
writel(0, espi->mmio + SSPCR1);
device_set_node(&host->dev, dev_fwnode(&pdev->dev));
error = devm_spi_register_controller(&pdev->dev, host);
if (error) {
dev_err(&pdev->dev, "failed to register SPI host\n");
@ -746,9 +719,16 @@ static void ep93xx_spi_remove(struct platform_device *pdev)
ep93xx_spi_release_dma(espi);
}
static const struct of_device_id ep93xx_spi_of_ids[] = {
{ .compatible = "cirrus,ep9301-spi" },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, ep93xx_spi_of_ids);
static struct platform_driver ep93xx_spi_driver = {
.driver = {
.name = "ep93xx-spi",
.of_match_table = ep93xx_spi_of_ids,
},
.probe = ep93xx_spi_probe,
.remove_new = ep93xx_spi_remove,