[PATCHv2] wlcore: spi: add wl18xx support

Reizer, Eyal
2016-04-10T07:37:31Z

Add support for using with both wl12xx and wl18xx.

- all wilink family needs special init command for entering wspi mode.
extra clock cycles should be sent after the spi init command while the
cs pin is high.
- switch to controling the cs pin from the spi driver for achieveing the
above.
- the selected cs gpio is read from the spi device-tree node using the
cs-gpios field and setup as a gpio.
- See the example below for specifying the cs gpio using the cs-gpios entry
&spi0 {
...
cs-gpios = <&gpio0 5 0>;
...
wlcore: wlcore@0 {
compatible = "ti,wl1835";
...
...
};
};

Signed-off-by: Eyal Reizer <eyalr@ti.com>
---
v1 -> v2: update device tree bindings documentation

.../bindings/net/wireless/ti,wlcore,spi.txt | 50 +++++-
drivers/net/wireless/ti/wlcore/spi.c | 176 +++++++++++++++++---
2 files changed, 200 insertions(+), 26 deletions(-)

diff --git a/Documentation/devicetree/bindings/net/wireless/ti,wlcore,spi.txt b/Documentation/devicetree/bindings/net/wireless/ti,wlcore,spi.txt
index 9180724..912ab0c 100644
--- a/Documentation/devicetree/bindings/net/wireless/ti,wlcore,spi.txt
+++ b/Documentation/devicetree/bindings/net/wireless/ti,wlcore,spi.txt
@@ -1,19 +1,31 @@
-* Texas Instruments wl1271 wireless lan controller
+* Texas Instruments wl12xx/wl18xx wireless lan controller

-The wl1271 chip can be connected via SPI or via SDIO. This
+The wl12xx/wl18xx chips can be connected via SPI or via SDIO. This
document describes the binding for the SPI connected chip.

Required properties:
-- compatible : Should be "ti,wl1271"
+- compatible : Should be one of the following:
+ * "ti,wl1271"
+ * "ti,wl1273"
+ * "ti,wl1281"
+ * "ti,wl1283"
+ * "ti,wl1801"
+ * "ti,wl1805"
+ * "ti,wl1807"
+ * "ti,wl1831"
+ * "ti,wl1835"
+ * "ti,wl1837"
- reg : Chip select address of device
- spi-max-frequency : Maximum SPI clocking speed of device in Hz
-- ref-clock-frequency : Reference clock frequency
- interrupt-parent, interrupts :
Should contain parameters for 1 interrupt line.
Interrupt parameters: parent, line number, type.
-- vwlan-supply : Point the node of the regulator that powers/enable the wl1271 chip
+- vwlan-supply : Point the node of the regulator that powers/enable the
+ wl12xx/wl18xx chip
+- cs-gpios : GPIO pin used as the spi chip select

Optional properties:
+- ref-clock-frequency : Reference clock frequency (should be set for wl12xx)
- clock-xtal : boolean, clock is generated from XTAL

- Please consult Documentation/devicetree/bindings/spi/spi-bus.txt
@@ -21,10 +33,16 @@ Optional properties:

Examples:

+For wl12xx family:
&spi1 {
- wl1271@1 {
+ status = "okay";
+ pinctrl-names = "default";
+ pinctrl-0 = <&spi1_pins>;
+ cs-gpios = <&gpio0 5 0>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ wlcore: wlcore@0 {
compatible = "ti,wl1271";
-
reg = <1>;
spi-max-frequency = <48000000>;
clock-xtal;
@@ -34,3 +52,21 @@ Examples:
vwlan-supply = <&vwlan_fixed>;
};
};
+
+For wl18xx family:
+&spi0 {
+ status = "okay";
+ pinctrl-names = "default";
+ pinctrl-0 = <&spi0_pins>;
+ cs-gpios = <&gpio0 5 0>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ wlcore: wlcore@0 {
+ compatible = "ti,wl1835";
+ vwlan-supply = <&wlan_en_reg>;
+ spi-max-frequency = <48000000>;
+ reg = <0>;
+ interrupt-parent = <&gpio0>;
+ interrupts = <27 IRQ_TYPE_EDGE_RISING>;
+ };
+};
diff --git a/drivers/net/wireless/ti/wlcore/spi.c b/drivers/net/wireless/ti/wlcore/spi.c
index 020ac1a..fb48a0d 100644
--- a/drivers/net/wireless/ti/wlcore/spi.c
+++ b/drivers/net/wireless/ti/wlcore/spi.c
@@ -32,6 +32,7 @@
#include <linux/platform_device.h>
#include <linux/of_irq.h>
#include <linux/regulator/consumer.h>
+#include <linux/gpio.h>

#include "wlcore.h"
#include "wl12xx_80211.h"
@@ -70,16 +71,30 @@
#define WSPI_MAX_CHUNK_SIZE 4092

/*
- * only support SPI for 12xx - this code should be reworked when 18xx
- * support is introduced
+ * wl18xx driver aggregation buffer size is (13 * PAGE_SIZE) compared to
+ * (4 * PAGE_SIZE) for wl12xx, so use the larger buffer needed for wl18xx
*/
-#define SPI_AGGR_BUFFER_SIZE (4 * PAGE_SIZE)
+#define SPI_AGGR_BUFFER_SIZE (13 * PAGE_SIZE)

/* Maximum number of SPI write chunks */
#define WSPI_MAX_NUM_OF_CHUNKS \
((SPI_AGGR_BUFFER_SIZE / WSPI_MAX_CHUNK_SIZE) + 1)

+struct wilink_familiy_data {
+ char name[8];
+};
+
+const struct wilink_familiy_data *wilink_data;
+
+static const struct wilink_familiy_data wl18xx_data = {
+ .name = "wl18xx",
+};
+
+static const struct wilink_familiy_data wl12xx_data = {
+ .name = "wl12xx",
+};
+
struct wl12xx_spi_glue {
struct device *dev;
struct platform_device *core;
@@ -120,6 +135,8 @@ static void wl12xx_spi_init(struct device *child)
struct spi_transfer t;
struct spi_message m;
u8 *cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
+ struct spi_device *spi = (struct spi_device *)glue->dev;
+ struct spi_master *master = spi->master;

if (!cmd) {
dev_err(child->parent,
@@ -127,6 +144,15 @@ static void wl12xx_spi_init(struct device *child)
return;
}

+ if (!master->cs_gpios) {
+ dev_err(child->parent,
+ "spi chip select pin missing in platform data!\n");
+ return;
+ }
+
+ /* Drive CS line low */
+ gpio_direction_output(master->cs_gpios[0], 0);
+
memset(&t, 0, sizeof(t));
spi_message_init(&m);

@@ -163,6 +189,26 @@ static void wl12xx_spi_init(struct device *child)
spi_message_add_tail(&t, &m);

spi_sync(to_spi_device(glue->dev), &m);
+
+ /* Send extra clocks with CS high. this is required by the wilink
+ * family in order for successfully enter WSPI mode
+ */
+ gpio_direction_output(master->cs_gpios[0], 1);
+
+ memset(&m, 0, sizeof(m));
+ spi_message_init(&m);
+
+ cmd[0] = 0xff;
+ cmd[1] = 0xff;
+ cmd[2] = 0xff;
+ cmd[3] = 0xff;
+ swab32s((u32 *)cmd);
+
+ t.tx_buf = cmd;
+ t.len = 4;
+ spi_message_add_tail(&t, &m);
+ spi_sync(to_spi_device(glue->dev), &m);
+
kfree(cmd);
}

@@ -213,6 +259,16 @@ static int __must_check wl12xx_spi_raw_read(struct device *child, int addr,
u32 *busy_buf;
u32 *cmd;
u32 chunk_len;
+ struct spi_device *spi = (struct spi_device *)glue->dev;
+ struct spi_master *master = spi->master;
+
+ if (!master->cs_gpios) {
+ dev_err(child->parent,
+ "spi chip select pin missing in platform data!\n");
+ return -EINVAL;
+ }
+ /* Drive CS line low */
+ gpio_direction_output(master->cs_gpios[0], 0);

while (len > 0) {
chunk_len = min_t(size_t, WSPI_MAX_CHUNK_SIZE, len);
@@ -267,25 +323,44 @@ static int __must_check wl12xx_spi_raw_read(struct device *child, int addr,
len -= chunk_len;
}

+ /* Drive CS line high */
+ gpio_direction_output(master->cs_gpios[0], 1);
return 0;
}

-static int __must_check wl12xx_spi_raw_write(struct device *child, int addr,
- void *buf, size_t len, bool fixed)
+static int __wl12xx_spi_raw_write(struct device *child, int addr,
+ void *buf, size_t len, bool fixed)
{
struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
- /* SPI write buffers - 2 for each chunk */
- struct spi_transfer t[2 * WSPI_MAX_NUM_OF_CHUNKS];
+ struct spi_transfer *t;
struct spi_message m;
u32 commands[WSPI_MAX_NUM_OF_CHUNKS]; /* 1 command per chunk */
u32 *cmd;
u32 chunk_len;
int i;
+ struct spi_device *spi = (struct spi_device *)glue->dev;
+ struct spi_master *master = spi->master;
+
+ if (!master->cs_gpios) {
+ dev_err(child->parent,
+ "spi chip select pin missing in platform data!\n");
+ return -EINVAL;
+ }
+
+ /* SPI write buffers - 2 for each chunk */
+ t = kzalloc(sizeof(*t) * 2 * WSPI_MAX_NUM_OF_CHUNKS, GFP_KERNEL);
+ if (!t) {
+ dev_err(child->parent,
+ "could not allocate spi write buffer\n");
+ return -ENOMEM;
+ }
+
+ /* Drive CS line low */
+ gpio_direction_output(master->cs_gpios[0], 0);

WARN_ON(len > SPI_AGGR_BUFFER_SIZE);

spi_message_init(&m);
- memset(t, 0, sizeof(t));

cmd = &commands[0];
i = 0;
@@ -318,9 +393,29 @@ static int __must_check wl12xx_spi_raw_write(struct device *child, int addr,

spi_sync(to_spi_device(glue->dev), &m);

+ /* Drive CS line high */
+ gpio_direction_output(master->cs_gpios[0], 1);
+
+ kfree(t);
return 0;
}

+static int __must_check wl12xx_spi_raw_write(struct device *child, int addr,
+ void *buf, size_t len, bool fixed)
+{
+ int ret;
+
+ /* The ELP wakeup write may fail the first time due to internal
+ * hardware latency. It is safer to send the wakeup command twice to
+ * avoid unexpected failures.
+ */
+ if (addr == HW_ACCESS_ELP_CTRL_REG)
+ ret = __wl12xx_spi_raw_write(child, addr, buf, len, fixed);
+ ret = __wl12xx_spi_raw_write(child, addr, buf, len, fixed);
+
+ return ret;
+}
+
/**
* wl12xx_spi_set_power - power on/off the wl12xx unit
* @child: wl12xx device handle.
@@ -349,17 +444,38 @@ static int wl12xx_spi_set_power(struct device *child, bool enable)
return ret;
}

+/**
+ * wl12xx_spi_set_block_size
+ *
+ * This function is not needed for spi mode, but need to be present.
+ * Without it defined the wlcore fallback to use the wrong packet
+ * allignment on tx.
+ */
+static void wl12xx_spi_set_block_size(struct device *child,
+ unsigned int blksz)
+{
+}
+
static struct wl1271_if_operations spi_ops = {
.read = wl12xx_spi_raw_read,
.write = wl12xx_spi_raw_write,
.reset = wl12xx_spi_reset,
.init = wl12xx_spi_init,
.power = wl12xx_spi_set_power,
- .set_block_size = NULL,
+ .set_block_size = wl12xx_spi_set_block_size,
};

static const struct of_device_id wlcore_spi_of_match_table[] = {
- { .compatible = "ti,wl1271" },
+ { .compatible = "ti,wl1271", .data = &wl12xx_data},
+ { .compatible = "ti,wl1273", .data = &wl12xx_data},
+ { .compatible = "ti,wl1281", .data = &wl12xx_data},
+ { .compatible = "ti,wl1283", .data = &wl12xx_data},
+ { .compatible = "ti,wl1801", .data = &wl18xx_data},
+ { .compatible = "ti,wl1805", .data = &wl18xx_data},
+ { .compatible = "ti,wl1807", .data = &wl18xx_data},
+ { .compatible = "ti,wl1831", .data = &wl18xx_data},
+ { .compatible = "ti,wl1835", .data = &wl18xx_data},
+ { .compatible = "ti,wl1837", .data = &wl18xx_data},
{ }
};
MODULE_DEVICE_TABLE(of, wlcore_spi_of_match_table);
@@ -375,18 +491,24 @@ static int wlcore_probe_of(struct spi_device *spi, struct wl12xx_spi_glue *glue,
struct wlcore_platdev_data *pdev_data)
{
struct device_node *dt_node = spi->dev.of_node;
- int ret;
+ const struct of_device_id *of_id;
+
+ of_id = of_match_node(wlcore_spi_of_match_table, dt_node);
+ if (!of_id)
+ return -ENODEV;
+
+ wilink_data = of_id->data;
+ dev_info(&spi->dev, "selected chip familiy is %s\n",
+ wilink_data->name);

if (of_find_property(dt_node, "clock-xtal", NULL))
pdev_data->ref_clock_xtal = true;

- ret = of_property_read_u32(dt_node, "ref-clock-frequency",
- &pdev_data->ref_clock_freq);
- if (IS_ERR_VALUE(ret)) {
- dev_err(glue->dev,
- "can't get reference clock frequency (%d)\n", ret);
- return ret;
- }
+ /* optional clock frequency params */
+ of_property_read_u32(dt_node, "ref-clock-frequency",
+ &pdev_data->ref_clock_freq);
+ of_property_read_u32(dt_node, "tcxo-clock-frequency",
+ &pdev_data->tcxo_clock_freq);

return 0;
}
@@ -397,6 +519,7 @@ static int wl1271_probe(struct spi_device *spi)
struct wlcore_platdev_data pdev_data;
struct resource res[1];
int ret;
+ struct spi_master *master = spi->master;

memset(&pdev_data, 0x00, sizeof(pdev_data));

@@ -410,6 +533,12 @@ static int wl1271_probe(struct spi_device *spi)

glue->dev = &spi->dev;

+ if (!master->cs_gpios) {
+ dev_err(glue->dev,
+ "spi chip select pin missing in platform data!\n");
+ return -EINVAL;
+ }
+
spi_set_drvdata(spi, glue);

/* This is the only SPI value that we need to set here, the rest
@@ -431,15 +560,21 @@ static int wl1271_probe(struct spi_device *spi)
return ret;
}

+ if (gpio_request(master->cs_gpios[0], "spi1-cs0"))
+ return -EINVAL;
+
ret = spi_setup(spi);
if (ret < 0) {
dev_err(glue->dev, "spi_setup failed\n");
+ gpio_free(master->cs_gpios[0]);
return ret;
}

- glue->core = platform_device_alloc("wl12xx", PLATFORM_DEVID_AUTO);
+ glue->core = platform_device_alloc(wilink_data->name,
+ PLATFORM_DEVID_AUTO);
if (!glue->core) {
dev_err(glue->dev, "can't allocate platform_device\n");
+ gpio_free(master->cs_gpios[0]);
return -ENOMEM;
}

@@ -474,14 +609,17 @@ static int wl1271_probe(struct spi_device *spi)

out_dev_put:
platform_device_put(glue->core);
+ gpio_free(master->cs_gpios[0]);
return ret;
}

static int wl1271_remove(struct spi_device *spi)
{
struct wl12xx_spi_glue *glue = spi_get_drvdata(spi);
+ struct spi_master *master = spi->master;

platform_device_unregister(glue->core);
+ gpio_free(master->cs_gpios[0]);

return 0;
}
--
1.7.9.5