summaryrefslogtreecommitdiffstats
path: root/drivers/i2c/i2c-slave-testunit.c
diff options
context:
space:
mode:
authorWolfram Sang <wsa+renesas@sang-engineering.com>2024-08-11 23:23:15 +0200
committerWolfram Sang <wsa+renesas@sang-engineering.com>2024-08-14 19:55:40 +0200
commit6b21470af096e7f3acc4f0521354c5b044e2372c (patch)
treed48cca6eae5227891de4a1350f3e9b2965205aef /drivers/i2c/i2c-slave-testunit.c
parenti2c: testunit: use decimal values in docs when appropriate (diff)
downloadlinux-6b21470af096e7f3acc4f0521354c5b044e2372c.tar.xz
linux-6b21470af096e7f3acc4f0521354c5b044e2372c.zip
i2c: testunit: add command to support versioning and test rep_start
For some devices, it is essential that controllers handle repeated start correctly and do not replace it with a stop/start combination. This addition helps to test that because it will only return a version string if repeated start is done properly. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Diffstat (limited to 'drivers/i2c/i2c-slave-testunit.c')
-rw-r--r--drivers/i2c/i2c-slave-testunit.c25
1 files changed, 23 insertions, 2 deletions
diff --git a/drivers/i2c/i2c-slave-testunit.c b/drivers/i2c/i2c-slave-testunit.c
index be1d2e900aef..51b399aa09a0 100644
--- a/drivers/i2c/i2c-slave-testunit.c
+++ b/drivers/i2c/i2c-slave-testunit.c
@@ -6,6 +6,7 @@
* Copyright (C) 2020 by Renesas Electronics Corporation
*/
+#include <generated/utsrelease.h>
#include <linux/bitops.h>
#include <linux/i2c.h>
#include <linux/init.h>
@@ -15,11 +16,13 @@
#include <linux/workqueue.h> /* FIXME: is system_long_wq the best choice? */
#define TU_CUR_VERSION 0x01
+#define TU_VERSION_MAX_LENGTH 128
enum testunit_cmds {
TU_CMD_READ_BYTES = 1, /* save 0 for ABORT, RESET or similar */
TU_CMD_SMBUS_HOST_NOTIFY,
TU_CMD_SMBUS_BLOCK_PROC_CALL,
+ TU_CMD_GET_VERSION_WITH_REP_START,
TU_NUM_CMDS
};
@@ -39,10 +42,13 @@ struct testunit_data {
unsigned long flags;
u8 regs[TU_NUM_REGS];
u8 reg_idx;
+ u8 read_idx;
struct i2c_client *client;
struct delayed_work worker;
};
+static char tu_version_info[] = "v" UTS_RELEASE "\n\0";
+
static void i2c_slave_testunit_work(struct work_struct *work)
{
struct testunit_data *tu = container_of(work, struct testunit_data, worker.work);
@@ -91,6 +97,8 @@ static int i2c_slave_testunit_slave_cb(struct i2c_client *client,
struct testunit_data *tu = i2c_get_clientdata(client);
bool is_proc_call = tu->reg_idx == 3 && tu->regs[TU_REG_DATAL] == 1 &&
tu->regs[TU_REG_CMD] == TU_CMD_SMBUS_BLOCK_PROC_CALL;
+ bool is_get_version = tu->reg_idx == 3 &&
+ tu->regs[TU_REG_CMD] == TU_CMD_GET_VERSION_WITH_REP_START;
int ret = 0;
switch (event) {
@@ -100,6 +108,7 @@ static int i2c_slave_testunit_slave_cb(struct i2c_client *client,
memset(tu->regs, 0, TU_NUM_REGS);
tu->reg_idx = 0;
+ tu->read_idx = 0;
break;
case I2C_SLAVE_WRITE_RECEIVED:
@@ -136,12 +145,21 @@ static int i2c_slave_testunit_slave_cb(struct i2c_client *client,
break;
case I2C_SLAVE_READ_PROCESSED:
- if (is_proc_call && tu->regs[TU_REG_DATAH])
+ /* Advance until we reach the NUL character */
+ if (is_get_version && tu_version_info[tu->read_idx] != 0)
+ tu->read_idx++;
+ else if (is_proc_call && tu->regs[TU_REG_DATAH])
tu->regs[TU_REG_DATAH]--;
+
fallthrough;
case I2C_SLAVE_READ_REQUESTED:
- *val = is_proc_call ? tu->regs[TU_REG_DATAH] : TU_CUR_VERSION;
+ if (is_get_version)
+ *val = tu_version_info[tu->read_idx];
+ else if (is_proc_call)
+ *val = tu->regs[TU_REG_DATAH];
+ else
+ *val = TU_CUR_VERSION;
break;
}
@@ -160,6 +178,9 @@ static int i2c_slave_testunit_probe(struct i2c_client *client)
i2c_set_clientdata(client, tu);
INIT_DELAYED_WORK(&tu->worker, i2c_slave_testunit_work);
+ if (sizeof(tu_version_info) > TU_VERSION_MAX_LENGTH)
+ tu_version_info[TU_VERSION_MAX_LENGTH - 1] = 0;
+
return i2c_slave_register(client, i2c_slave_testunit_slave_cb);
};