From a14a569a9918a0c7e340257a17dbc088bb27db72 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Thomas=20Wei=C3=9Fschuh?= Date: Wed, 29 May 2024 08:27:11 +0200 Subject: [PATCH] platform/chrome: cros_ec_proto: Introduce cros_ec_cmd_readmem() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit To read from the EC memory different mechanism are possible. ECs connected via LPC expose their memory via a ->cmd_readmem operation. Other protocols require the usage of EC_CMD_READ_MEMMAP, which on the other hand is not implemented by LPC ECs. Provide a helper that automatically selects the correct mechanism. Signed-off-by: Thomas Weißschuh Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/20240529-cros_ec-hwmon-v4-1-5cdf0c5db50a@weissschuh.net Signed-off-by: Tzung-Bi Shih --- drivers/platform/chrome/cros_ec_proto.c | 27 +++++++++++++++++++++ include/linux/platform_data/cros_ec_proto.h | 2 ++ 2 files changed, 29 insertions(+) diff --git a/drivers/platform/chrome/cros_ec_proto.c b/drivers/platform/chrome/cros_ec_proto.c index dcfc18fe1cdf..2ad1b8221ec0 100644 --- a/drivers/platform/chrome/cros_ec_proto.c +++ b/drivers/platform/chrome/cros_ec_proto.c @@ -1033,3 +1033,30 @@ error: return ret; } EXPORT_SYMBOL_GPL(cros_ec_cmd); + +/** + * cros_ec_cmd_readmem - Read from EC memory. + * + * @ec_dev: EC device + * @offset: Is within EC_LPC_ADDR_MEMMAP region. + * @size: Number of bytes to read. + * @dest: EC command output data + * + * Return: >= 0 on success, negative error number on failure. + */ +int cros_ec_cmd_readmem(struct cros_ec_device *ec_dev, u8 offset, u8 size, void *dest) +{ + struct ec_params_read_memmap params = {}; + + if (!size) + return -EINVAL; + + if (ec_dev->cmd_readmem) + return ec_dev->cmd_readmem(ec_dev, offset, size, dest); + + params.offset = offset; + params.size = size; + return cros_ec_cmd(ec_dev, 0, EC_CMD_READ_MEMMAP, + ¶ms, sizeof(params), dest, size); +} +EXPORT_SYMBOL_GPL(cros_ec_cmd_readmem); diff --git a/include/linux/platform_data/cros_ec_proto.h b/include/linux/platform_data/cros_ec_proto.h index 8865e350c12a..1ddc52603f9a 100644 --- a/include/linux/platform_data/cros_ec_proto.h +++ b/include/linux/platform_data/cros_ec_proto.h @@ -261,6 +261,8 @@ int cros_ec_get_sensor_count(struct cros_ec_dev *ec); int cros_ec_cmd(struct cros_ec_device *ec_dev, unsigned int version, int command, const void *outdata, size_t outsize, void *indata, size_t insize); +int cros_ec_cmd_readmem(struct cros_ec_device *ec_dev, u8 offset, u8 size, void *dest); + /** * cros_ec_get_time_ns() - Return time in ns. *