[PATCH v2 05/12] spi: mxs-spi: move to use generic DMA helper
Shawn Guo
shawn.guo at linaro.org
Tue Mar 5 07:23:57 EST 2013
With the generic DMA device tree helper supported by mxs-dma driver,
client devices only need to call dma_request_slave_channel() for
requesting a DMA channel from dmaengine.
Since mxs is a DT only platform now, along with the changes, the non-DT
case handling in probe function also gets removed.
Signed-off-by: Shawn Guo <shawn.guo at linaro.org>
Acked-by: Grant Likely <grant.likely at secretlab.ca>
---
Documentation/devicetree/bindings/spi/mxs-spi.txt | 12 +++--
drivers/spi/spi-mxs.c | 60 ++++-----------------
include/linux/spi/mxs-spi.h | 4 +-
3 files changed, 18 insertions(+), 58 deletions(-)
diff --git a/Documentation/devicetree/bindings/spi/mxs-spi.txt b/Documentation/devicetree/bindings/spi/mxs-spi.txt
index e2e1395..3499b73 100644
--- a/Documentation/devicetree/bindings/spi/mxs-spi.txt
+++ b/Documentation/devicetree/bindings/spi/mxs-spi.txt
@@ -3,8 +3,11 @@
Required properties:
- compatible: Should be "fsl,<soc>-spi", where soc is "imx23" or "imx28"
- reg: Offset and length of the register set for the device
-- interrupts: Should contain SSP interrupts (error irq first, dma irq second)
-- fsl,ssp-dma-channel: APBX DMA channel for the SSP
+- interrupts: Should contain SSP ERROR interrupt
+- dmas: DMA specifier, consisting of a phandle to DMA controller node
+ and SSP DMA channel ID.
+ Refer to dma.txt and fsl-mxs-dma.txt for details.
+- dma-names: Must be "rx-tx".
Optional properties:
- clock-frequency : Input clock frequency to the SPI block in Hz.
@@ -17,6 +20,7 @@ ssp0: ssp at 80010000 {
#size-cells = <0>;
compatible = "fsl,imx28-spi";
reg = <0x80010000 0x2000>;
- interrupts = <96 82>;
- fsl,ssp-dma-channel = <0>;
+ interrupts = <96>;
+ dmas = <&dma_apbh 0>;
+ dma-names = "rx-tx";
};
diff --git a/drivers/spi/spi-mxs.c b/drivers/spi/spi-mxs.c
index 22a0af0..7b1c014 100644
--- a/drivers/spi/spi-mxs.c
+++ b/drivers/spi/spi-mxs.c
@@ -490,21 +490,6 @@ static int mxs_spi_transfer_one(struct spi_master *master,
return status;
}
-static bool mxs_ssp_dma_filter(struct dma_chan *chan, void *param)
-{
- struct mxs_ssp *ssp = param;
-
- if (!mxs_dma_is_apbh(chan))
- return false;
-
- if (chan->chan_id != ssp->dma_channel)
- return false;
-
- chan->private = &ssp->dma_data;
-
- return true;
-}
-
static const struct of_device_id mxs_spi_dt_ids[] = {
{ .compatible = "fsl,imx23-spi", .data = (void *) IMX23_SSP, },
{ .compatible = "fsl,imx28-spi", .data = (void *) IMX28_SSP, },
@@ -520,13 +505,12 @@ static int mxs_spi_probe(struct platform_device *pdev)
struct spi_master *master;
struct mxs_spi *spi;
struct mxs_ssp *ssp;
- struct resource *iores, *dmares;
+ struct resource *iores;
struct pinctrl *pinctrl;
struct clk *clk;
void __iomem *base;
- int devid, dma_channel, clk_freq;
- int ret = 0, irq_err, irq_dma;
- dma_cap_mask_t mask;
+ int devid, clk_freq;
+ int ret = 0, irq_err;
/*
* Default clock speed for the SPI core. 160MHz seems to
@@ -537,8 +521,7 @@ static int mxs_spi_probe(struct platform_device *pdev)
iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
irq_err = platform_get_irq(pdev, 0);
- irq_dma = platform_get_irq(pdev, 1);
- if (!iores || irq_err < 0 || irq_dma < 0)
+ if (!iores || irq_err < 0)
return -EINVAL;
base = devm_ioremap_resource(&pdev->dev, iores);
@@ -553,32 +536,11 @@ static int mxs_spi_probe(struct platform_device *pdev)
if (IS_ERR(clk))
return PTR_ERR(clk);
- if (np) {
- devid = (enum mxs_ssp_id) of_id->data;
- /*
- * TODO: This is a temporary solution and should be changed
- * to use generic DMA binding later when the helpers get in.
- */
- ret = of_property_read_u32(np, "fsl,ssp-dma-channel",
- &dma_channel);
- if (ret) {
- dev_err(&pdev->dev,
- "Failed to get DMA channel\n");
- return -EINVAL;
- }
-
- ret = of_property_read_u32(np, "clock-frequency",
- &clk_freq);
- if (ret)
- clk_freq = clk_freq_default;
- } else {
- dmares = platform_get_resource(pdev, IORESOURCE_DMA, 0);
- if (!dmares)
- return -EINVAL;
- devid = pdev->id_entry->driver_data;
- dma_channel = dmares->start;
+ devid = (enum mxs_ssp_id) of_id->data;
+ ret = of_property_read_u32(np, "clock-frequency",
+ &clk_freq);
+ if (ret)
clk_freq = clk_freq_default;
- }
master = spi_alloc_master(&pdev->dev, sizeof(*spi));
if (!master)
@@ -597,7 +559,6 @@ static int mxs_spi_probe(struct platform_device *pdev)
ssp->clk = clk;
ssp->base = base;
ssp->devid = devid;
- ssp->dma_channel = dma_channel;
init_completion(&spi->c);
@@ -606,10 +567,7 @@ static int mxs_spi_probe(struct platform_device *pdev)
if (ret)
goto out_master_free;
- dma_cap_zero(mask);
- dma_cap_set(DMA_SLAVE, mask);
- ssp->dma_data.chan_irq = irq_dma;
- ssp->dmach = dma_request_channel(mask, mxs_ssp_dma_filter, ssp);
+ ssp->dmach = dma_request_slave_channel(&pdev->dev, "rx-tx");
if (!ssp->dmach) {
dev_err(ssp->dev, "Failed to request DMA\n");
goto out_master_free;
diff --git a/include/linux/spi/mxs-spi.h b/include/linux/spi/mxs-spi.h
index 61ae130..4835486 100644
--- a/include/linux/spi/mxs-spi.h
+++ b/include/linux/spi/mxs-spi.h
@@ -24,7 +24,7 @@
#ifndef __LINUX_SPI_MXS_SPI_H__
#define __LINUX_SPI_MXS_SPI_H__
-#include <linux/fsl/mxs-dma.h>
+#include <linux/dmaengine.h>
#define ssp_is_old(host) ((host)->devid == IMX23_SSP)
@@ -137,9 +137,7 @@ struct mxs_ssp {
unsigned int clk_rate;
enum mxs_ssp_id devid;
- int dma_channel;
struct dma_chan *dmach;
- struct mxs_dma_data dma_data;
unsigned int dma_dir;
enum dma_transfer_direction slave_dirn;
u32 ssp_pio_words[SSP_PIO_NUM];
--
1.7.9.5
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