From: Jérôme Pouiller <jerome.pouiller@xxxxxxxxxx> Signed-off-by: Jérôme Pouiller <jerome.pouiller@xxxxxxxxxx> --- drivers/net/wireless/silabs/wfx/bus_spi.c | 297 ++++++++++++++++++++++ 1 file changed, 297 insertions(+) create mode 100644 drivers/net/wireless/silabs/wfx/bus_spi.c diff --git a/drivers/net/wireless/silabs/wfx/bus_spi.c b/drivers/net/wireless/silabs/wfx/bus_spi.c new file mode 100644 index 000000000000..6b4f9fff8b44 --- /dev/null +++ b/drivers/net/wireless/silabs/wfx/bus_spi.c @@ -0,0 +1,297 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * SPI interface. + * + * Copyright (c) 2017-2020, Silicon Laboratories, Inc. + * Copyright (c) 2011, Sagrad Inc. + * Copyright (c) 2010, ST-Ericsson + */ +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/gpio/consumer.h> +#include <linux/spi/spi.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/of.h> + +#include "bus.h" +#include "wfx.h" +#include "hwio.h" +#include "main.h" +#include "bh.h" + +#define SET_WRITE 0x7FFF /* usage: and operation */ +#define SET_READ 0x8000 /* usage: or operation */ + +static const struct wfx_platform_data pdata_wf200 = { + .file_fw = "wfx/wfm_wf200", + .file_pds = "wfx/wf200.pds", + .use_rising_clk = true, +}; + +static const struct wfx_platform_data pdata_brd4001a = { + .file_fw = "wfx/wfm_wf200", + .file_pds = "wfx/brd4001a.pds", + .use_rising_clk = true, +}; + +static const struct wfx_platform_data pdata_brd8022a = { + .file_fw = "wfx/wfm_wf200", + .file_pds = "wfx/brd8022a.pds", + .use_rising_clk = true, +}; + +static const struct wfx_platform_data pdata_brd8023a = { + .file_fw = "wfx/wfm_wf200", + .file_pds = "wfx/brd8023a.pds", + .use_rising_clk = true, +}; + +/* Legacy DT don't use it */ +static const struct wfx_platform_data pdata_wfx_spi = { + .file_fw = "wfm_wf200", + .file_pds = "wf200.pds", + .use_rising_clk = true, + .reset_inverted = true, +}; + +struct wfx_spi_priv { + struct spi_device *func; + struct wfx_dev *core; + struct gpio_desc *gpio_reset; + bool need_swab; +}; + +/* The chip reads 16bits of data at time and place them directly into (little endian) CPU register. + * So, the chip expects bytes order to be "B1 B0 B3 B2" (while LE is "B0 B1 B2 B3" and BE is + * "B3 B2 B1 B0") + * + * A little endian host with bits_per_word == 16 should do the right job natively. The code below to + * support big endian host and commonly used SPI 8bits. + */ +static int wfx_spi_copy_from_io(void *priv, unsigned int addr, void *dst, size_t count) +{ + struct wfx_spi_priv *bus = priv; + u16 regaddr = (addr << 12) | (count / 2) | SET_READ; + 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, + }; + u16 *dst16 = dst; + int ret, i; + + WARN(count % 2, "buffer size must be a multiple of 2"); + + cpu_to_le16s(®addr); + if (bus->need_swab) + swab16s(®addr); + + spi_message_init(&m); + spi_message_add_tail(&t_addr, &m); + spi_message_add_tail(&t_msg, &m); + ret = spi_sync(bus->func, &m); + + if (bus->need_swab && addr == WFX_REG_CONFIG) + for (i = 0; i < count / 2; i++) + swab16s(&dst16[i]); + return ret; +} + +static int wfx_spi_copy_to_io(void *priv, unsigned int addr, const void *src, size_t count) +{ + struct wfx_spi_priv *bus = priv; + u16 regaddr = (addr << 12) | (count / 2); + /* FIXME: use a bounce buffer */ + u16 *src16 = (void *)src; + int ret, i; + struct spi_message m; + struct spi_transfer t_addr = { + .tx_buf = ®addr, + .len = sizeof(regaddr), + }; + struct spi_transfer t_msg = { + .tx_buf = src, + .len = count, + }; + + WARN(count % 2, "buffer size must be a multiple of 2"); + WARN(regaddr & SET_READ, "bad addr or size overflow"); + + cpu_to_le16s(®addr); + + /* Register address and CONFIG content always use 16bit big endian + * ("BADC" order) + */ + if (bus->need_swab) + swab16s(®addr); + if (bus->need_swab && addr == WFX_REG_CONFIG) + for (i = 0; i < count / 2; i++) + swab16s(&src16[i]); + + spi_message_init(&m); + spi_message_add_tail(&t_addr, &m); + spi_message_add_tail(&t_msg, &m); + ret = spi_sync(bus->func, &m); + + if (bus->need_swab && addr == WFX_REG_CONFIG) + for (i = 0; i < count / 2; i++) + swab16s(&src16[i]); + return ret; +} + +static void wfx_spi_lock(void *priv) +{ +} + +static void wfx_spi_unlock(void *priv) +{ +} + +static irqreturn_t wfx_spi_irq_handler(int irq, void *priv) +{ + struct wfx_spi_priv *bus = priv; + + wfx_bh_request_rx(bus->core); + return IRQ_HANDLED; +} + +static int wfx_spi_irq_subscribe(void *priv) +{ + struct wfx_spi_priv *bus = priv; + u32 flags; + + flags = irq_get_trigger_type(bus->func->irq); + if (!flags) + flags = IRQF_TRIGGER_HIGH; + flags |= IRQF_ONESHOT; + return devm_request_threaded_irq(&bus->func->dev, bus->func->irq, NULL, + wfx_spi_irq_handler, IRQF_ONESHOT, "wfx", bus); +} + +static int wfx_spi_irq_unsubscribe(void *priv) +{ + struct wfx_spi_priv *bus = priv; + + devm_free_irq(&bus->func->dev, bus->func->irq, bus); + return 0; +} + +static size_t wfx_spi_align_size(void *priv, size_t size) +{ + /* Most of SPI controllers avoid DMA if buffer size is not 32bit aligned */ + return ALIGN(size, 4); +} + +static const struct wfx_hwbus_ops wfx_spi_hwbus_ops = { + .copy_from_io = wfx_spi_copy_from_io, + .copy_to_io = wfx_spi_copy_to_io, + .irq_subscribe = wfx_spi_irq_subscribe, + .irq_unsubscribe = wfx_spi_irq_unsubscribe, + .lock = wfx_spi_lock, + .unlock = wfx_spi_unlock, + .align_size = wfx_spi_align_size, +}; + +static int wfx_spi_probe(struct spi_device *func) +{ + struct wfx_platform_data *pdata; + struct wfx_spi_priv *bus; + int ret; + + if (!func->bits_per_word) + func->bits_per_word = 16; + ret = spi_setup(func); + if (ret) + return ret; + pdata = (struct wfx_platform_data *)spi_get_device_id(func)->driver_data; + if (!pdata) { + dev_err(&func->dev, "unable to retrieve driver data (please report)\n"); + return -ENODEV; + } + + /* Trace below is also displayed by spi_setup() if compiled with DEBUG */ + dev_dbg(&func->dev, "SPI params: CS=%d, mode=%d bits/word=%d speed=%d\n", + func->chip_select, func->mode, func->bits_per_word, func->max_speed_hz); + if (func->bits_per_word != 16 && func->bits_per_word != 8) + dev_warn(&func->dev, "unusual bits/word value: %d\n", func->bits_per_word); + if (func->max_speed_hz > 50000000) + dev_warn(&func->dev, "%dHz is a very high speed\n", func->max_speed_hz); + + bus = devm_kzalloc(&func->dev, sizeof(*bus), GFP_KERNEL); + if (!bus) + return -ENOMEM; + bus->func = func; + if (func->bits_per_word == 8 || IS_ENABLED(CONFIG_CPU_BIG_ENDIAN)) + bus->need_swab = true; + spi_set_drvdata(func, bus); + + bus->gpio_reset = devm_gpiod_get_optional(&func->dev, "reset", GPIOD_OUT_LOW); + if (IS_ERR(bus->gpio_reset)) + return PTR_ERR(bus->gpio_reset); + if (!bus->gpio_reset) { + dev_warn(&func->dev, "gpio reset is not defined, trying to load firmware anyway\n"); + } else { + gpiod_set_consumer_name(bus->gpio_reset, "wfx reset"); + if (pdata->reset_inverted) + gpiod_toggle_active_low(bus->gpio_reset); + gpiod_set_value_cansleep(bus->gpio_reset, 1); + usleep_range(100, 150); + gpiod_set_value_cansleep(bus->gpio_reset, 0); + usleep_range(2000, 2500); + } + + bus->core = wfx_init_common(&func->dev, pdata, &wfx_spi_hwbus_ops, bus); + if (!bus->core) + return -EIO; + + return wfx_probe(bus->core); +} + +static int wfx_spi_remove(struct spi_device *func) +{ + struct wfx_spi_priv *bus = spi_get_drvdata(func); + + wfx_release(bus->core); + return 0; +} + +/* For dynamic driver binding, kernel does not use OF to match driver. It only + * use modalias and modalias is a copy of 'compatible' DT node with vendor + * stripped. + */ +static const struct spi_device_id wfx_spi_id[] = { + { "wf200", (kernel_ulong_t)&pdata_wf200 }, + { "brd4001a", (kernel_ulong_t)&pdata_brd4001a }, + { "brd8022a", (kernel_ulong_t)&pdata_brd8022a }, + { "brd8023a", (kernel_ulong_t)&pdata_brd8023a }, + { "wfx-spi", (kernel_ulong_t)&pdata_wfx_spi }, + { }, +}; +MODULE_DEVICE_TABLE(spi, wfx_spi_id); + +#ifdef CONFIG_OF +static const struct of_device_id wfx_spi_of_match[] = { + { .compatible = "silabs,wf200" }, + { .compatible = "silabs,brd4001a" }, + { .compatible = "silabs,brd8022a" }, + { .compatible = "silabs,brd8023a" }, + { .compatible = "silabs,wfx-spi" }, + { }, +}; +MODULE_DEVICE_TABLE(of, wfx_spi_of_match); +#endif + +struct spi_driver wfx_spi_driver = { + .driver = { + .name = "wfx-spi", + .of_match_table = of_match_ptr(wfx_spi_of_match), + }, + .id_table = wfx_spi_id, + .probe = wfx_spi_probe, + .remove = wfx_spi_remove, +}; -- 2.34.1