diff options
Diffstat (limited to 'drivers/soundwire/debugfs.c')
| -rw-r--r-- | drivers/soundwire/debugfs.c | 150 |
1 files changed, 150 insertions, 0 deletions
diff --git a/drivers/soundwire/debugfs.c b/drivers/soundwire/debugfs.c index 67abd7e52f09..6d253d69871d 100644 --- a/drivers/soundwire/debugfs.c +++ b/drivers/soundwire/debugfs.c @@ -3,6 +3,7 @@ #include <linux/device.h> #include <linux/debugfs.h> +#include <linux/firmware.h> #include <linux/mod_devicetable.h> #include <linux/pm_runtime.h> #include <linux/slab.h> @@ -137,6 +138,145 @@ static int sdw_slave_reg_show(struct seq_file *s_file, void *data) } DEFINE_SHOW_ATTRIBUTE(sdw_slave_reg); +#define MAX_CMD_BYTES 256 + +static int cmd; +static u32 start_addr; +static size_t num_bytes; +static u8 read_buffer[MAX_CMD_BYTES]; +static char *firmware_file; + +static int set_command(void *data, u64 value) +{ + struct sdw_slave *slave = data; + + if (value > 1) + return -EINVAL; + + /* Userspace changed the hardware state behind the kernel's back */ + add_taint(TAINT_USER, LOCKDEP_STILL_OK); + + dev_dbg(&slave->dev, "command: %s\n", value ? "read" : "write"); + cmd = value; + + return 0; +} +DEFINE_DEBUGFS_ATTRIBUTE(set_command_fops, NULL, + set_command, "%llu\n"); + +static int set_start_address(void *data, u64 value) +{ + struct sdw_slave *slave = data; + + /* Userspace changed the hardware state behind the kernel's back */ + add_taint(TAINT_USER, LOCKDEP_STILL_OK); + + dev_dbg(&slave->dev, "start address %#llx\n", value); + + start_addr = value; + + return 0; +} +DEFINE_DEBUGFS_ATTRIBUTE(set_start_address_fops, NULL, + set_start_address, "%llu\n"); + +static int set_num_bytes(void *data, u64 value) +{ + struct sdw_slave *slave = data; + + if (value == 0 || value > MAX_CMD_BYTES) + return -EINVAL; + + /* Userspace changed the hardware state behind the kernel's back */ + add_taint(TAINT_USER, LOCKDEP_STILL_OK); + + dev_dbg(&slave->dev, "number of bytes %lld\n", value); + + num_bytes = value; + + return 0; +} +DEFINE_DEBUGFS_ATTRIBUTE(set_num_bytes_fops, NULL, + set_num_bytes, "%llu\n"); + +static int cmd_go(void *data, u64 value) +{ + struct sdw_slave *slave = data; + int ret; + + if (value != 1) + return -EINVAL; + + /* one last check */ + if (start_addr > SDW_REG_MAX || + num_bytes == 0 || num_bytes > MAX_CMD_BYTES) + return -EINVAL; + + ret = pm_runtime_get_sync(&slave->dev); + if (ret < 0 && ret != -EACCES) { + pm_runtime_put_noidle(&slave->dev); + return ret; + } + + /* Userspace changed the hardware state behind the kernel's back */ + add_taint(TAINT_USER, LOCKDEP_STILL_OK); + + dev_dbg(&slave->dev, "starting command\n"); + + if (cmd == 0) { + const struct firmware *fw; + + ret = request_firmware(&fw, firmware_file, &slave->dev); + if (ret < 0) { + dev_err(&slave->dev, "firmware %s not found\n", firmware_file); + goto out; + } + + if (fw->size != num_bytes) { + dev_err(&slave->dev, + "firmware %s: unexpected size %zd, desired %zd\n", + firmware_file, fw->size, num_bytes); + release_firmware(fw); + goto out; + } + + ret = sdw_nwrite_no_pm(slave, start_addr, num_bytes, fw->data); + release_firmware(fw); + } else { + ret = sdw_nread_no_pm(slave, start_addr, num_bytes, read_buffer); + } + + dev_dbg(&slave->dev, "command completed %d\n", ret); + +out: + pm_runtime_mark_last_busy(&slave->dev); + pm_runtime_put(&slave->dev); + + return ret; +} +DEFINE_DEBUGFS_ATTRIBUTE(cmd_go_fops, NULL, + cmd_go, "%llu\n"); + +#define MAX_LINE_LEN 128 + +static int read_buffer_show(struct seq_file *s_file, void *data) +{ + char buf[MAX_LINE_LEN]; + int i; + + if (num_bytes == 0 || num_bytes > MAX_CMD_BYTES) + return -EINVAL; + + for (i = 0; i < num_bytes; i++) { + scnprintf(buf, MAX_LINE_LEN, "address %#x val 0x%02x\n", + start_addr + i, read_buffer[i]); + seq_printf(s_file, "%s", buf); + } + + return 0; +} +DEFINE_SHOW_ATTRIBUTE(read_buffer); + void sdw_slave_debugfs_init(struct sdw_slave *slave) { struct dentry *master; @@ -151,6 +291,16 @@ void sdw_slave_debugfs_init(struct sdw_slave *slave) debugfs_create_file("registers", 0400, d, slave, &sdw_slave_reg_fops); + /* interface to send arbitrary commands */ + debugfs_create_file("command", 0200, d, slave, &set_command_fops); + debugfs_create_file("start_address", 0200, d, slave, &set_start_address_fops); + debugfs_create_file("num_bytes", 0200, d, slave, &set_num_bytes_fops); + debugfs_create_file("go", 0200, d, slave, &cmd_go_fops); + + debugfs_create_file("read_buffer", 0400, d, slave, &read_buffer_fops); + firmware_file = NULL; + debugfs_create_str("firmware_file", 0200, d, &firmware_file); + slave->debugfs = d; } |