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-rw-r--r--Documentation/devicetree/bindings/arm/primecell.txt19
-rw-r--r--Documentation/devicetree/bindings/serial/pl011.txt17
-rw-r--r--Documentation/devicetree/bindings/spi/spi_pl022.txt36
-rw-r--r--drivers/spi/spi-pl022.c43
-rw-r--r--drivers/tty/serial/amba-pl011.c62
5 files changed, 149 insertions, 28 deletions
diff --git a/Documentation/devicetree/bindings/arm/primecell.txt b/Documentation/devicetree/bindings/arm/primecell.txt
index 64fc82bc8928..0df6acacfaea 100644
--- a/Documentation/devicetree/bindings/arm/primecell.txt
+++ b/Documentation/devicetree/bindings/arm/primecell.txt
@@ -16,14 +16,31 @@ Optional properties:
- clocks : From common clock binding. First clock is phandle to clock for apb
pclk. Additional clocks are optional and specific to those peripherals.
- clock-names : From common clock binding. Shall be "apb_pclk" for first clock.
+- dmas : From common DMA binding. If present, refers to one or more dma channels.
+- dma-names : From common DMA binding, needs to match the 'dmas' property.
+ Devices with exactly one receive and transmit channel shall name
+ these "rx" and "tx", respectively.
+- pinctrl-<n> : Pinctrl states as described in bindings/pinctrl/pinctrl-bindings.txt
+- pinctrl-names : Names corresponding to the numbered pinctrl states
+- interrupts : one or more interrupt specifiers
+- interrupt-names : names corresponding to the interrupts properties
Example:
serial@fff36000 {
compatible = "arm,pl011", "arm,primecell";
arm,primecell-periphid = <0x00341011>;
+
clocks = <&pclk>;
clock-names = "apb_pclk";
-
+
+ dmas = <&dma-controller 4>, <&dma-controller 5>;
+ dma-names = "rx", "tx";
+
+ pinctrl-0 = <&uart0_default_mux>, <&uart0_default_mode>;
+ pinctrl-1 = <&uart0_sleep_mode>;
+ pinctrl-names = "default","sleep";
+
+ interrupts = <0 11 0x4>;
};
diff --git a/Documentation/devicetree/bindings/serial/pl011.txt b/Documentation/devicetree/bindings/serial/pl011.txt
new file mode 100644
index 000000000000..5d2e840ae65c
--- /dev/null
+++ b/Documentation/devicetree/bindings/serial/pl011.txt
@@ -0,0 +1,17 @@
+* ARM AMBA Primecell PL011 serial UART
+
+Required properties:
+- compatible: must be "arm,primecell", "arm,pl011"
+- reg: exactly one register range with length 0x1000
+- interrupts: exactly one interrupt specifier
+
+Optional properties:
+- pinctrl: When present, must have one state named "sleep"
+ and one state named "default"
+- clocks: When present, must refer to exactly one clock named
+ "apb_pclk"
+- dmas: When present, may have one or two dma channels.
+ The first one must be named "rx", the second one
+ must be named "tx".
+
+See also bindings/arm/primecell.txt
diff --git a/Documentation/devicetree/bindings/spi/spi_pl022.txt b/Documentation/devicetree/bindings/spi/spi_pl022.txt
index f158fd31cfda..22ed6797216d 100644
--- a/Documentation/devicetree/bindings/spi/spi_pl022.txt
+++ b/Documentation/devicetree/bindings/spi/spi_pl022.txt
@@ -16,6 +16,11 @@ Optional properties:
device will be suspended immediately
- pl022,rt : indicates the controller should run the message pump with realtime
priority to minimise the transfer latency on the bus (boolean)
+- dmas : Two or more DMA channel specifiers following the convention outlined
+ in bindings/dma/dma.txt
+- dma-names: Names for the dma channels, if present. There must be at
+ least one channel named "tx" for transmit and named "rx" for
+ receive.
SPI slave nodes must be children of the SPI master node and can
@@ -32,3 +37,34 @@ contain the following properties.
- pl022,wait-state : Microwire interface: Wait state
- pl022,duplex : Microwire interface: Full/Half duplex
+
+Example:
+
+ spi@e0100000 {
+ compatible = "arm,pl022", "arm,primecell";
+ reg = <0xe0100000 0x1000>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ interrupts = <0 31 0x4>;
+ dmas = <&dma-controller 23 1>,
+ <&dma-controller 24 0>;
+ dma-names = "rx", "tx";
+
+ m25p80@1 {
+ compatible = "st,m25p80";
+ reg = <1>;
+ spi-max-frequency = <12000000>;
+ spi-cpol;
+ spi-cpha;
+ pl022,hierarchy = <0>;
+ pl022,interface = <0>;
+ pl022,slave-tx-disable;
+ pl022,com-mode = <0x2>;
+ pl022,rx-level-trig = <0>;
+ pl022,tx-level-trig = <0>;
+ pl022,ctrl-len = <0x11>;
+ pl022,wait-state = <0>;
+ pl022,duplex = <0>;
+ };
+ };
+
diff --git a/drivers/spi/spi-pl022.c b/drivers/spi/spi-pl022.c
index b0fe393c882c..371cc66f1a0e 100644
--- a/drivers/spi/spi-pl022.c
+++ b/drivers/spi/spi-pl022.c
@@ -1139,6 +1139,35 @@ err_no_rxchan:
return -ENODEV;
}
+static int pl022_dma_autoprobe(struct pl022 *pl022)
+{
+ struct device *dev = &pl022->adev->dev;
+
+ /* automatically configure DMA channels from platform, normally using DT */
+ pl022->dma_rx_channel = dma_request_slave_channel(dev, "rx");
+ if (!pl022->dma_rx_channel)
+ goto err_no_rxchan;
+
+ pl022->dma_tx_channel = dma_request_slave_channel(dev, "tx");
+ if (!pl022->dma_tx_channel)
+ goto err_no_txchan;
+
+ pl022->dummypage = kmalloc(PAGE_SIZE, GFP_KERNEL);
+ if (!pl022->dummypage)
+ goto err_no_dummypage;
+
+ return 0;
+
+err_no_dummypage:
+ dma_release_channel(pl022->dma_tx_channel);
+ pl022->dma_tx_channel = NULL;
+err_no_txchan:
+ dma_release_channel(pl022->dma_rx_channel);
+ pl022->dma_rx_channel = NULL;
+err_no_rxchan:
+ return -ENODEV;
+}
+
static void terminate_dma(struct pl022 *pl022)
{
struct dma_chan *rxchan = pl022->dma_rx_channel;
@@ -1167,6 +1196,11 @@ static inline int configure_dma(struct pl022 *pl022)
return -ENODEV;
}
+static inline int pl022_dma_autoprobe(struct pl022 *pl022)
+{
+ return 0;
+}
+
static inline int pl022_dma_probe(struct pl022 *pl022)
{
return 0;
@@ -2226,8 +2260,13 @@ static int pl022_probe(struct amba_device *adev, const struct amba_id *id)
goto err_no_irq;
}
- /* Get DMA channels */
- if (platform_info->enable_dma) {
+ /* Get DMA channels, try autoconfiguration first */
+ status = pl022_dma_autoprobe(pl022);
+
+ /* If that failed, use channels from platform_info */
+ if (status == 0)
+ platform_info->enable_dma = 1;
+ else if (platform_info->enable_dma) {
status = pl022_dma_probe(pl022);
if (status != 0)
platform_info->enable_dma = 0;
diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index 3ea5408fcbeb..c25b00ef9dbb 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -245,7 +245,7 @@ static void pl011_sgbuf_free(struct dma_chan *chan, struct pl011_sgbuf *sg,
}
}
-static void pl011_dma_probe_initcall(struct uart_amba_port *uap)
+static void pl011_dma_probe_initcall(struct device *dev, struct uart_amba_port *uap)
{
/* DMA is the sole user of the platform data right now */
struct amba_pl011_data *plat = uap->port.dev->platform_data;
@@ -259,20 +259,25 @@ static void pl011_dma_probe_initcall(struct uart_amba_port *uap)
struct dma_chan *chan;
dma_cap_mask_t mask;
- /* We need platform data */
- if (!plat || !plat->dma_filter) {
- dev_info(uap->port.dev, "no DMA platform data\n");
- return;
- }
+ chan = dma_request_slave_channel(dev, "tx");
- /* Try to acquire a generic DMA engine slave TX channel */
- dma_cap_zero(mask);
- dma_cap_set(DMA_SLAVE, mask);
-
- chan = dma_request_channel(mask, plat->dma_filter, plat->dma_tx_param);
if (!chan) {
- dev_err(uap->port.dev, "no TX DMA channel!\n");
- return;
+ /* We need platform data */
+ if (!plat || !plat->dma_filter) {
+ dev_info(uap->port.dev, "no DMA platform data\n");
+ return;
+ }
+
+ /* Try to acquire a generic DMA engine slave TX channel */
+ dma_cap_zero(mask);
+ dma_cap_set(DMA_SLAVE, mask);
+
+ chan = dma_request_channel(mask, plat->dma_filter,
+ plat->dma_tx_param);
+ if (!chan) {
+ dev_err(uap->port.dev, "no TX DMA channel!\n");
+ return;
+ }
}
dmaengine_slave_config(chan, &tx_conf);
@@ -282,7 +287,18 @@ static void pl011_dma_probe_initcall(struct uart_amba_port *uap)
dma_chan_name(uap->dmatx.chan));
/* Optionally make use of an RX channel as well */
- if (plat->dma_rx_param) {
+ chan = dma_request_slave_channel(dev, "rx");
+
+ if (!chan && plat->dma_rx_param) {
+ chan = dma_request_channel(mask, plat->dma_filter, plat->dma_rx_param);
+
+ if (!chan) {
+ dev_err(uap->port.dev, "no RX DMA channel!\n");
+ return;
+ }
+ }
+
+ if (chan) {
struct dma_slave_config rx_conf = {
.src_addr = uap->port.mapbase + UART01x_DR,
.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE,
@@ -291,12 +307,6 @@ static void pl011_dma_probe_initcall(struct uart_amba_port *uap)
.device_fc = false,
};
- chan = dma_request_channel(mask, plat->dma_filter, plat->dma_rx_param);
- if (!chan) {
- dev_err(uap->port.dev, "no RX DMA channel!\n");
- return;
- }
-
dmaengine_slave_config(chan, &rx_conf);
uap->dmarx.chan = chan;
@@ -315,6 +325,7 @@ static void pl011_dma_probe_initcall(struct uart_amba_port *uap)
struct dma_uap {
struct list_head node;
struct uart_amba_port *uap;
+ struct device *dev;
};
static LIST_HEAD(pl011_dma_uarts);
@@ -325,7 +336,7 @@ static int __init pl011_dma_initcall(void)
list_for_each_safe(node, tmp, &pl011_dma_uarts) {
struct dma_uap *dmau = list_entry(node, struct dma_uap, node);
- pl011_dma_probe_initcall(dmau->uap);
+ pl011_dma_probe_initcall(dmau->dev, dmau->uap);
list_del(node);
kfree(dmau);
}
@@ -334,18 +345,19 @@ static int __init pl011_dma_initcall(void)
device_initcall(pl011_dma_initcall);
-static void pl011_dma_probe(struct uart_amba_port *uap)
+static void pl011_dma_probe(struct device *dev, struct uart_amba_port *uap)
{
struct dma_uap *dmau = kzalloc(sizeof(struct dma_uap), GFP_KERNEL);
if (dmau) {
dmau->uap = uap;
+ dmau->dev = dev;
list_add_tail(&dmau->node, &pl011_dma_uarts);
}
}
#else
-static void pl011_dma_probe(struct uart_amba_port *uap)
+static void pl011_dma_probe(struct device *dev, struct uart_amba_port *uap)
{
- pl011_dma_probe_initcall(uap);
+ pl011_dma_probe_initcall(dev, uap);
}
#endif
@@ -2020,7 +2032,7 @@ static int pl011_probe(struct amba_device *dev, const struct amba_id *id)
uap->port.ops = &amba_pl011_pops;
uap->port.flags = UPF_BOOT_AUTOCONF;
uap->port.line = i;
- pl011_dma_probe(uap);
+ pl011_dma_probe(&dev->dev, uap);
/* Ensure interrupts from this UART are masked and cleared */
writew(0, uap->port.membase + UART011_IMSC);