| /* |
| * 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 const 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; |
| } |
| |
| static int __maybe_unused 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); |
| |
| static struct spi_driver spi_driver = { |
| .probe = cw1200_spi_probe, |
| .remove = cw1200_spi_disconnect, |
| .driver = { |
| .name = "cw1200_wlan_spi", |
| .pm = IS_ENABLED(CONFIG_PM) ? &cw1200_pm_ops : NULL, |
| }, |
| }; |
| |
| module_spi_driver(spi_driver); |