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spi: sh-msiof: Add DT support to DMA setup

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Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@linaro.org>
This commit is contained in:
Geert Uytterhoeven 2014-08-06 14:59:05 +02:00 committed by Mark Brown
parent 52fba2b85d
commit a6be4de6a2
2 changed files with 32 additions and 10 deletions
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17
Documentation/devicetree/bindings/spi/sh-msiof.txt
View file

@ -6,8 +6,13 @@ Required properties:
"renesas,sh-mobile-msiof" for SH Mobile series.
Examples with soctypes are:
"renesas,msiof-r8a7790" (R-Car H2)
"renesas,msiof-r8a7791" (R-Car M2)
- reg : Offset and length of the register set for the device
- reg : A list of offsets and lengths of the register sets for
the device.
If only one register set is present, it is to be used
by both the CPU and the DMA engine.
If two register sets are present, the first is to be
used by the CPU, and the second is to be used by the
DMA engine.
- interrupt-parent : The phandle for the interrupt controller that
services interrupts for this device
- interrupts : Interrupt specifier
@ -17,6 +22,10 @@ Required properties:
Optional properties:
- clocks : Must contain a reference to the functional clock.
- num-cs : Total number of chip-selects (default is 1)
- dmas : Must contain a list of two references to DMA
specifiers, one for transmission, and one for
reception.
- dma-names : Must contain a list of two DMA names, "tx" and "rx".
Optional properties, deprecated for soctype-specific bindings:
- renesas,tx-fifo-size : Overrides the default tx fifo size given in words
@ -31,9 +40,11 @@ Example:
msiof0: spi@e6e20000 {
compatible = "renesas,msiof-r8a7791";
reg = <0 0xe6e20000 0 0x0064>;
reg = <0 0xe6e20000 0 0x0064>, <0 0xe7e20000 0 0x0064>;
interrupts = <0 156 IRQ_TYPE_LEVEL_HIGH>;
clocks = <&mstp0_clks R8A7791_CLK_MSIOF0>;
dmas = <&dmac0 0x51>, <&dmac0 0x52>;
dma-names = "tx", "rx";
#address-cells = <1>;
#size-cells = <0>;
status = "disabled";

25
drivers/spi/spi-sh-msiof.c
View file

@ -977,10 +977,11 @@ static struct dma_chan *sh_msiof_request_dma_chan(struct device *dev,
dma_cap_zero(mask);
dma_cap_set(DMA_SLAVE, mask);
chan = dma_request_channel(mask, shdma_chan_filter,
(void *)(unsigned long)id);
chan = dma_request_slave_channel_compat(mask, shdma_chan_filter,
(void *)(unsigned long)id, dev,
dir == DMA_MEM_TO_DEV ? "tx" : "rx");
if (!chan) {
dev_warn(dev, "dma_request_channel failed\n");
dev_warn(dev, "dma_request_slave_channel_compat failed\n");
return NULL;
}
@ -1010,12 +1011,22 @@ static int sh_msiof_request_dma(struct sh_msiof_spi_priv *p)
struct platform_device *pdev = p->pdev;
struct device *dev = &pdev->dev;
const struct sh_msiof_spi_info *info = dev_get_platdata(dev);
unsigned int dma_tx_id, dma_rx_id;
const struct resource *res;
struct spi_master *master;
struct device *tx_dev, *rx_dev;
if (!info || !info->dma_tx_id || !info->dma_rx_id)
return 0; /* The driver assumes no error */
if (dev->of_node) {
/* In the OF case we will get the slave IDs from the DT */
dma_tx_id = 0;
dma_rx_id = 0;
} else if (info && info->dma_tx_id && info->dma_rx_id) {
dma_tx_id = info->dma_tx_id;
dma_rx_id = info->dma_rx_id;
} else {
/* The driver assumes no error */
return 0;
}
/* The DMA engine uses the second register set, if present */
res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
@ -1024,13 +1035,13 @@ static int sh_msiof_request_dma(struct sh_msiof_spi_priv *p)
master = p->master;
master->dma_tx = sh_msiof_request_dma_chan(dev, DMA_MEM_TO_DEV,
info->dma_tx_id,
dma_tx_id,
res->start + TFDR);
if (!master->dma_tx)
return -ENODEV;
master->dma_rx = sh_msiof_request_dma_chan(dev, DMA_DEV_TO_MEM,
info->dma_rx_id,
dma_rx_id,
res->start + RFDR);
if (!master->dma_rx)
goto free_tx_chan;