--- /dev/null
+/*
+ * Mac80211 SPI driver for ST-Ericsson CW1200 device
+ *
+ * Copyright (c) 2011, Sagrad Inc.
+ * Author: Solomon Peachy <speachy@sagrad.com>
+ *
+ * Based on cw1200_sdio.c
+ * Copyright (c) 2010, ST-Ericsson
+ * Author: Dmitry Tarnyagin <dmitry.tarnyagin@lockless.no>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/gpio.h>
+#include <linux/delay.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+#include <net/mac80211.h>
+
+#include <linux/spi/spi.h>
+#include <linux/device.h>
+
+#include "cw1200.h"
+#include "hwbus.h"
+#include <linux/platform_data/net-cw1200.h>
+#include "hwio.h"
+
+MODULE_AUTHOR("Solomon Peachy <speachy@sagrad.com>");
+MODULE_DESCRIPTION("mac80211 ST-Ericsson CW1200 SPI driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("spi:cw1200_wlan_spi");
+
+/* #define SPI_DEBUG */
+
+struct hwbus_priv {
+ struct spi_device *func;
+ struct cw1200_common *core;
+ const struct cw1200_platform_data_spi *pdata;
+ spinlock_t lock; /* Serialize all bus operations */
+ wait_queue_head_t wq;
+ int claimed;
+};
+
+#define SDIO_TO_SPI_ADDR(addr) ((addr & 0x1f)>>2)
+#define SET_WRITE 0x7FFF /* usage: and operation */
+#define SET_READ 0x8000 /* usage: or operation */
+
+/* Notes on byte ordering:
+ LE: B0 B1 B2 B3
+ BE: B3 B2 B1 B0
+
+ Hardware expects 32-bit data to be written as 16-bit BE words:
+
+ B1 B0 B3 B2
+*/
+
+static int cw1200_spi_memcpy_fromio(struct hwbus_priv *self,
+ unsigned int addr,
+ void *dst, int count)
+{
+ int ret, i;
+ u16 regaddr;
+ struct spi_message m;
+
+ struct spi_transfer t_addr = {
+ .tx_buf = ®addr,
+ .len = sizeof(regaddr),
+ };
+ struct spi_transfer t_msg = {
+ .rx_buf = dst,
+ .len = count,
+ };
+
+ regaddr = (SDIO_TO_SPI_ADDR(addr))<<12;
+ regaddr |= SET_READ;
+ regaddr |= (count>>1);
+
+#ifdef SPI_DEBUG
+ pr_info("READ : %04d from 0x%02x (%04x)\n", count, addr, regaddr);
+#endif
+
+ /* Header is LE16 */
+ regaddr = cpu_to_le16(regaddr);
+
+ /* We have to byteswap if the SPI bus is limited to 8b operation
+ or we are running on a Big Endian system
+ */
+#if defined(__LITTLE_ENDIAN)
+ if (self->func->bits_per_word == 8)
+#endif
+ regaddr = swab16(regaddr);
+
+ spi_message_init(&m);
+ spi_message_add_tail(&t_addr, &m);
+ spi_message_add_tail(&t_msg, &m);
+ ret = spi_sync(self->func, &m);
+
+#ifdef SPI_DEBUG
+ pr_info("READ : ");
+ for (i = 0; i < t_addr.len; i++)
+ printk("%02x ", ((u8 *)t_addr.tx_buf)[i]);
+ printk(" : ");
+ for (i = 0; i < t_msg.len; i++)
+ printk("%02x ", ((u8 *)t_msg.rx_buf)[i]);
+ printk("\n");
+#endif
+
+ /* We have to byteswap if the SPI bus is limited to 8b operation
+ or we are running on a Big Endian system
+ */
+#if defined(__LITTLE_ENDIAN)
+ if (self->func->bits_per_word == 8)
+#endif
+ {
+ uint16_t *buf = (uint16_t *)dst;
+ for (i = 0; i < ((count + 1) >> 1); i++)
+ buf[i] = swab16(buf[i]);
+ }
+
+ return ret;
+}
+
+static int cw1200_spi_memcpy_toio(struct hwbus_priv *self,
+ unsigned int addr,
+ const void *src, int count)
+{
+ int rval, i;
+ u16 regaddr;
+ struct spi_transfer t_addr = {
+ .tx_buf = ®addr,
+ .len = sizeof(regaddr),
+ };
+ struct spi_transfer t_msg = {
+ .tx_buf = src,
+ .len = count,
+ };
+ struct spi_message m;
+
+ regaddr = (SDIO_TO_SPI_ADDR(addr))<<12;
+ regaddr &= SET_WRITE;
+ regaddr |= (count>>1);
+
+#ifdef SPI_DEBUG
+ pr_info("WRITE: %04d to 0x%02x (%04x)\n", count, addr, regaddr);
+#endif
+
+ /* Header is LE16 */
+ regaddr = cpu_to_le16(regaddr);
+
+ /* We have to byteswap if the SPI bus is limited to 8b operation
+ or we are running on a Big Endian system
+ */
+#if defined(__LITTLE_ENDIAN)
+ if (self->func->bits_per_word == 8)
+#endif
+ {
+ uint16_t *buf = (uint16_t *)src;
+ regaddr = swab16(regaddr);
+ for (i = 0; i < ((count + 1) >> 1); i++)
+ buf[i] = swab16(buf[i]);
+ }
+
+#ifdef SPI_DEBUG
+ pr_info("WRITE: ");
+ for (i = 0; i < t_addr.len; i++)
+ printk("%02x ", ((u8 *)t_addr.tx_buf)[i]);
+ printk(" : ");
+ for (i = 0; i < t_msg.len; i++)
+ printk("%02x ", ((u8 *)t_msg.tx_buf)[i]);
+ printk("\n");
+#endif
+
+ spi_message_init(&m);
+ spi_message_add_tail(&t_addr, &m);
+ spi_message_add_tail(&t_msg, &m);
+ rval = spi_sync(self->func, &m);
+
+#ifdef SPI_DEBUG
+ pr_info("WROTE: %d\n", m.actual_length);
+#endif
+
+#if defined(__LITTLE_ENDIAN)
+ /* We have to byteswap if the SPI bus is limited to 8b operation */
+ if (self->func->bits_per_word == 8)
+#endif
+ {
+ uint16_t *buf = (uint16_t *)src;
+ for (i = 0; i < ((count + 1) >> 1); i++)
+ buf[i] = swab16(buf[i]);
+ }
+ return rval;
+}
+
+static void cw1200_spi_lock(struct hwbus_priv *self)
+{
+ unsigned long flags;
+
+ DECLARE_WAITQUEUE(wait, current);
+
+ might_sleep();
+
+ add_wait_queue(&self->wq, &wait);
+ spin_lock_irqsave(&self->lock, flags);
+ while (1) {
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ if (!self->claimed)
+ break;
+ spin_unlock_irqrestore(&self->lock, flags);
+ schedule();
+ spin_lock_irqsave(&self->lock, flags);
+ }
+ set_current_state(TASK_RUNNING);
+ self->claimed = 1;
+ spin_unlock_irqrestore(&self->lock, flags);
+ remove_wait_queue(&self->wq, &wait);
+
+ return;
+}
+
+static void cw1200_spi_unlock(struct hwbus_priv *self)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&self->lock, flags);
+ self->claimed = 0;
+ spin_unlock_irqrestore(&self->lock, flags);
+ wake_up(&self->wq);
+
+ return;
+}
+
+static irqreturn_t cw1200_spi_irq_handler(int irq, void *dev_id)
+{
+ struct hwbus_priv *self = dev_id;
+
+ if (self->core) {
+ cw1200_spi_lock(self);
+ cw1200_irq_handler(self->core);
+ cw1200_spi_unlock(self);
+ return IRQ_HANDLED;
+ } else {
+ return IRQ_NONE;
+ }
+}
+
+static int cw1200_spi_irq_subscribe(struct hwbus_priv *self)
+{
+ int ret;
+
+ pr_debug("SW IRQ subscribe\n");
+
+ ret = request_threaded_irq(self->func->irq, NULL,
+ cw1200_spi_irq_handler,
+ IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
+ "cw1200_wlan_irq", self);
+ if (WARN_ON(ret < 0))
+ goto exit;
+
+ ret = enable_irq_wake(self->func->irq);
+ if (WARN_ON(ret))
+ goto free_irq;
+
+ return 0;
+
+free_irq:
+ free_irq(self->func->irq, self);
+exit:
+ return ret;
+}
+
+static int cw1200_spi_irq_unsubscribe(struct hwbus_priv *self)
+{
+ int ret = 0;
+
+ pr_debug("SW IRQ unsubscribe\n");
+ disable_irq_wake(self->func->irq);
+ free_irq(self->func->irq, self);
+
+ return ret;
+}
+
+static int cw1200_spi_off(const struct cw1200_platform_data_spi *pdata)
+{
+ if (pdata->reset) {
+ gpio_set_value(pdata->reset, 0);
+ msleep(30); /* Min is 2 * CLK32K cycles */
+ gpio_free(pdata->reset);
+ }
+
+ if (pdata->power_ctrl)
+ pdata->power_ctrl(pdata, false);
+ if (pdata->clk_ctrl)
+ pdata->clk_ctrl(pdata, false);
+
+ return 0;
+}
+
+static int cw1200_spi_on(const struct cw1200_platform_data_spi *pdata)
+{
+ /* Ensure I/Os are pulled low */
+ if (pdata->reset) {
+ gpio_request(pdata->reset, "cw1200_wlan_reset");
+ gpio_direction_output(pdata->reset, 0);
+ }
+ if (pdata->powerup) {
+ gpio_request(pdata->powerup, "cw1200_wlan_powerup");
+ gpio_direction_output(pdata->powerup, 0);
+ }
+ if (pdata->reset || pdata->powerup)
+ msleep(10); /* Settle time? */
+
+ /* Enable 3v3 and 1v8 to hardware */
+ if (pdata->power_ctrl) {
+ if (pdata->power_ctrl(pdata, true)) {
+ pr_err("power_ctrl() failed!\n");
+ return -1;
+ }
+ }
+
+ /* Enable CLK32K */
+ if (pdata->clk_ctrl) {
+ if (pdata->clk_ctrl(pdata, true)) {
+ pr_err("clk_ctrl() failed!\n");
+ return -1;
+ }
+ msleep(10); /* Delay until clock is stable for 2 cycles */
+ }
+
+ /* Enable POWERUP signal */
+ if (pdata->powerup) {
+ gpio_set_value(pdata->powerup, 1);
+ msleep(250); /* or more..? */
+ }
+ /* Enable RSTn signal */
+ if (pdata->reset) {
+ gpio_set_value(pdata->reset, 1);
+ msleep(50); /* Or more..? */
+ }
+ return 0;
+}
+
+static size_t cw1200_spi_align_size(struct hwbus_priv *self, size_t size)
+{
+ return size & 1 ? size + 1 : size;
+}
+
+static int cw1200_spi_pm(struct hwbus_priv *self, bool suspend)
+{
+ return irq_set_irq_wake(self->func->irq, suspend);
+}
+
+static struct hwbus_ops cw1200_spi_hwbus_ops = {
+ .hwbus_memcpy_fromio = cw1200_spi_memcpy_fromio,
+ .hwbus_memcpy_toio = cw1200_spi_memcpy_toio,
+ .lock = cw1200_spi_lock,
+ .unlock = cw1200_spi_unlock,
+ .align_size = cw1200_spi_align_size,
+ .power_mgmt = cw1200_spi_pm,
+};
+
+/* Probe Function to be called by SPI stack when device is discovered */
+static int cw1200_spi_probe(struct spi_device *func)
+{
+ const struct cw1200_platform_data_spi *plat_data =
+ dev_get_platdata(&func->dev);
+ struct hwbus_priv *self;
+ int status;
+
+ /* Sanity check speed */
+ if (func->max_speed_hz > 52000000)
+ func->max_speed_hz = 52000000;
+ if (func->max_speed_hz < 1000000)
+ func->max_speed_hz = 1000000;
+
+ /* Fix up transfer size */
+ if (plat_data->spi_bits_per_word)
+ func->bits_per_word = plat_data->spi_bits_per_word;
+ if (!func->bits_per_word)
+ func->bits_per_word = 16;
+
+ /* And finally.. */
+ func->mode = SPI_MODE_0;
+
+ pr_info("cw1200_wlan_spi: Probe called (CS %d M %d BPW %d CLK %d)\n",
+ func->chip_select, func->mode, func->bits_per_word,
+ func->max_speed_hz);
+
+ if (cw1200_spi_on(plat_data)) {
+ pr_err("spi_on() failed!\n");
+ return -1;
+ }
+
+ if (spi_setup(func)) {
+ pr_err("spi_setup() failed!\n");
+ return -1;
+ }
+
+ self = devm_kzalloc(&func->dev, sizeof(*self), GFP_KERNEL);
+ if (!self) {
+ pr_err("Can't allocate SPI hwbus_priv.");
+ return -ENOMEM;
+ }
+
+ self->pdata = plat_data;
+ self->func = func;
+ spin_lock_init(&self->lock);
+
+ spi_set_drvdata(func, self);
+
+ init_waitqueue_head(&self->wq);
+
+ status = cw1200_spi_irq_subscribe(self);
+
+ status = cw1200_core_probe(&cw1200_spi_hwbus_ops,
+ self, &func->dev, &self->core,
+ self->pdata->ref_clk,
+ self->pdata->macaddr,
+ self->pdata->sdd_file,
+ self->pdata->have_5ghz);
+
+ if (status) {
+ cw1200_spi_irq_unsubscribe(self);
+ cw1200_spi_off(plat_data);
+ }
+
+ return status;
+}
+
+/* Disconnect Function to be called by SPI stack when device is disconnected */
+static int cw1200_spi_disconnect(struct spi_device *func)
+{
+ struct hwbus_priv *self = spi_get_drvdata(func);
+
+ if (self) {
+ cw1200_spi_irq_unsubscribe(self);
+ if (self->core) {
+ cw1200_core_release(self->core);
+ self->core = NULL;
+ }
+ }
+ cw1200_spi_off(dev_get_platdata(&func->dev));
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int cw1200_spi_suspend(struct device *dev)
+{
+ struct hwbus_priv *self = spi_get_drvdata(to_spi_device(dev));
+
+ if (!cw1200_can_suspend(self->core))
+ return -EAGAIN;
+
+ /* XXX notify host that we have to keep CW1200 powered on? */
+ return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(cw1200_pm_ops, cw1200_spi_suspend, NULL);
+
+#endif
+
+static struct spi_driver spi_driver = {
+ .probe = cw1200_spi_probe,
+ .remove = cw1200_spi_disconnect,
+ .driver = {
+ .name = "cw1200_wlan_spi",
+ .bus = &spi_bus_type,
+ .owner = THIS_MODULE,
+#ifdef CONFIG_PM
+ .pm = &cw1200_pm_ops,
+#endif
+ },
+};
+
+module_spi_driver(spi_driver);
Code Review / kvmfornfv.git / blobdiff