Add initial support for the new Goodix "Berlin" touchscreen ICs over the SPI interface. The driver doesn't use the regmap_spi code since the SPI messages needs to be prefixed, thus this custom regmap code. This initial driver is derived from the Goodix goodix_ts_berlin available at [1] and [2] and only supports the GT9916 IC present on the Qualcomm SM8550 MTP & QRD touch panel. The current implementation only supports BerlinD, aka GT9916. [1] https://github.com/goodix/goodix_ts_berlin [2] https://git.codelinaro.org/clo/la/platform/vendor/opensource/touch-drivers Signed-off-by: Neil Armstrong <neil.armstrong@xxxxxxxxxx> --- drivers/input/touchscreen/Kconfig | 13 ++ drivers/input/touchscreen/Makefile | 1 + drivers/input/touchscreen/goodix_berlin_spi.c | 172 ++++++++++++++++++++++++++ 3 files changed, 186 insertions(+) diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig index 5e21cca6025d..2d86615e5090 100644 --- a/drivers/input/touchscreen/Kconfig +++ b/drivers/input/touchscreen/Kconfig @@ -435,6 +435,19 @@ config TOUCHSCREEN_GOODIX_BERLIN_I2C To compile this driver as a module, choose M here: the module will be called goodix_berlin_i2c. +config TOUCHSCREEN_GOODIX_BERLIN_SPI + tristate "Goodix Berlin SPI touchscreen" + depends on SPI_MASTER + select TOUCHSCREEN_GOODIX_BERLIN_CORE + help + Say Y here if you have a Goodix Berlin IC connected to + your system via SPI. + + If unsure, say N. + + To compile this driver as a module, choose M here: the + module will be called goodix_berlin_spi. + config TOUCHSCREEN_HIDEEP tristate "HiDeep Touch IC" depends on I2C diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile index 921a2da0c2be..29524e8a83db 100644 --- a/drivers/input/touchscreen/Makefile +++ b/drivers/input/touchscreen/Makefile @@ -49,6 +49,7 @@ obj-$(CONFIG_TOUCHSCREEN_FUJITSU) += fujitsu_ts.o obj-$(CONFIG_TOUCHSCREEN_GOODIX) += goodix_ts.o obj-$(CONFIG_TOUCHSCREEN_GOODIX_BERLIN_CORE) += goodix_berlin_core.o obj-$(CONFIG_TOUCHSCREEN_GOODIX_BERLIN_I2C) += goodix_berlin_i2c.o +obj-$(CONFIG_TOUCHSCREEN_GOODIX_BERLIN_SPI) += goodix_berlin_spi.o obj-$(CONFIG_TOUCHSCREEN_HIDEEP) += hideep.o obj-$(CONFIG_TOUCHSCREEN_HYNITRON_CSTXXX) += hynitron_cstxxx.o obj-$(CONFIG_TOUCHSCREEN_ILI210X) += ili210x.o diff --git a/drivers/input/touchscreen/goodix_berlin_spi.c b/drivers/input/touchscreen/goodix_berlin_spi.c new file mode 100644 index 000000000000..3a1bc251b32d --- /dev/null +++ b/drivers/input/touchscreen/goodix_berlin_spi.c @@ -0,0 +1,172 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Goodix Berlin Touchscreen Driver + * + * Copyright (C) 2020 - 2021 Goodix, Inc. + * Copyright (C) 2023 Linaro Ltd. + * + * Based on goodix_ts_berlin driver. + */ +#include <asm/unaligned.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/regmap.h> +#include <linux/spi/spi.h> + +#include "goodix_berlin.h" + +#define SPI_TRANS_PREFIX_LEN 1 +#define REGISTER_WIDTH 4 +#define SPI_READ_DUMMY_LEN 3 +#define SPI_READ_PREFIX_LEN (SPI_TRANS_PREFIX_LEN + REGISTER_WIDTH + SPI_READ_DUMMY_LEN) +#define SPI_WRITE_PREFIX_LEN (SPI_TRANS_PREFIX_LEN + REGISTER_WIDTH) + +#define SPI_WRITE_FLAG 0xF0 +#define SPI_READ_FLAG 0xF1 + +static int goodix_berlin_spi_read(void *context, const void *reg_buf, + size_t reg_size, void *val_buf, + size_t val_size) +{ + struct spi_device *spi = context; + struct spi_transfer xfers; + struct spi_message spi_msg; + const u32 *reg = reg_buf; /* reg is stored as native u32 at start of buffer */ + u8 *buf; + int ret; + + if (reg_size != REGISTER_WIDTH) + return -EINVAL; + + buf = kzalloc(SPI_READ_PREFIX_LEN + val_size, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + spi_message_init(&spi_msg); + memset(&xfers, 0, sizeof(xfers)); + + /* buffer format: 0xF1 + addr(4bytes) + dummy(3bytes) + data */ + buf[0] = SPI_READ_FLAG; + put_unaligned_be32(*reg, buf + SPI_TRANS_PREFIX_LEN); + memset(buf + SPI_TRANS_PREFIX_LEN + REGISTER_WIDTH, 0xff, + SPI_READ_DUMMY_LEN); + + xfers.tx_buf = buf; + xfers.rx_buf = buf; + xfers.len = SPI_READ_PREFIX_LEN + val_size; + xfers.cs_change = 0; + spi_message_add_tail(&xfers, &spi_msg); + + ret = spi_sync(spi, &spi_msg); + if (ret < 0) + dev_err(&spi->dev, "transfer error:%d", ret); + else + memcpy(val_buf, buf + SPI_READ_PREFIX_LEN, val_size); + + kfree(buf); + return ret; +} + +static int goodix_berlin_spi_write(void *context, const void *data, + size_t count) +{ + unsigned int len = count - REGISTER_WIDTH; + struct spi_device *spi = context; + struct spi_transfer xfers; + struct spi_message spi_msg; + const u32 *reg = data; /* reg is stored as native u32 at start of buffer */ + u8 *buf; + int ret; + + buf = kzalloc(SPI_WRITE_PREFIX_LEN + len, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + spi_message_init(&spi_msg); + memset(&xfers, 0, sizeof(xfers)); + + buf[0] = SPI_WRITE_FLAG; + put_unaligned_be32(*reg, buf + SPI_TRANS_PREFIX_LEN); + memcpy(buf + SPI_WRITE_PREFIX_LEN, data + REGISTER_WIDTH, len); + + xfers.tx_buf = buf; + xfers.len = SPI_WRITE_PREFIX_LEN + len; + xfers.cs_change = 0; + spi_message_add_tail(&xfers, &spi_msg); + + ret = spi_sync(spi, &spi_msg); + if (ret < 0) + dev_err(&spi->dev, "transfer error:%d", ret); + + kfree(buf); + return ret; +} + +static const struct regmap_config goodix_berlin_spi_regmap_conf = { + .reg_bits = 32, + .val_bits = 8, + .read = goodix_berlin_spi_read, + .write = goodix_berlin_spi_write, +}; + +/* vendor & product left unassigned here, should probably be updated from fw info */ +static const struct input_id goodix_berlin_spi_input_id = { + .bustype = BUS_SPI, +}; + +static int goodix_berlin_spi_probe(struct spi_device *spi) +{ + struct regmap_config *regmap_config; + struct regmap *regmap; + size_t max_size; + int error = 0; + + regmap_config = devm_kmemdup(&spi->dev, &goodix_berlin_spi_regmap_conf, + sizeof(*regmap_config), GFP_KERNEL); + if (!regmap_config) + return -ENOMEM; + + spi->mode = SPI_MODE_0; + spi->bits_per_word = 8; + error = spi_setup(spi); + if (error) + return error; + + max_size = spi_max_transfer_size(spi); + regmap_config->max_raw_read = max_size - SPI_READ_PREFIX_LEN; + regmap_config->max_raw_write = max_size - SPI_WRITE_PREFIX_LEN; + + regmap = devm_regmap_init(&spi->dev, NULL, spi, regmap_config); + if (IS_ERR(regmap)) + return PTR_ERR(regmap); + + return goodix_berlin_probe(&spi->dev, spi->irq, + &goodix_berlin_spi_input_id, regmap); +} + +static const struct spi_device_id goodix_berlin_spi_ids[] = { + { "gt9916" }, + { }, +}; +MODULE_DEVICE_TABLE(spi, goodix_berlin_spi_ids); + +static const struct of_device_id goodix_berlin_spi_of_match[] = { + { .compatible = "goodix,gt9916", }, + { } +}; +MODULE_DEVICE_TABLE(of, goodix_berlin_spi_of_match); + +static struct spi_driver goodix_berlin_spi_driver = { + .driver = { + .name = "goodix-berlin-spi", + .of_match_table = goodix_berlin_spi_of_match, + .pm = pm_sleep_ptr(&goodix_berlin_pm_ops), + }, + .probe = goodix_berlin_spi_probe, + .id_table = goodix_berlin_spi_ids, +}; +module_spi_driver(goodix_berlin_spi_driver); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Goodix Berlin SPI Touchscreen driver"); +MODULE_AUTHOR("Neil Armstrong <neil.armstrong@xxxxxxxxxx>"); -- 2.34.1
