sensor sc3336驱动bug

[lzjie-tchip]

kernel-6.1调试发现如果没有扫描到i2c id而进入__sc3336_power_off时会发生报错：

[    2.394164] sc3336 4-0030: driver version: 00.01.01
[    2.394254] sc3336 4-0030: could not get default pinstate
[    2.394260] sc3336 4-0030: could not get sleep pinstate
[    2.394286] sc3336 4-0030: supply avdd not found, using dummy regulator
[    2.394356] sc3336 4-0030: supply dovdd not found, using dummy regulator
[    2.394386] sc3336 4-0030: supply dvdd not found, using dummy regulator
[    2.396719] mmc_host mmc1: Bus speed (slot 0) = 400000Hz (slot req 400000Hz, actual 400000HZ div = 0)
[    2.402530] sc3336 4-0030: Unexpected sensor id(000000), ret(-5)
[    2.402556] ------------[ cut here ]------------
[    2.402560] WARNING: CPU: 5 PID: 1 at drivers/regulator/core.c:2411 _regulator_put.part.0+0x158/0x160
[    2.402572] Modules linked in:
[    2.402577] CPU: 5 PID: 1 Comm: swapper/0 Not tainted 6.1.84 #179
[    2.402583] Hardware name: Firefly EXT-iCore-3576Q38 Linux (DT)
[    2.402587] pstate: 80000005 (Nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[    2.402592] pc : _regulator_put.part.0+0x158/0x160
[    2.402597] lr : regulator_bulk_free+0x64/0x8c
[    2.402601] sp : ffffffc00afbbac0
[    2.402605] x29: ffffffc00afbbac0 x28: 0000000000000000 x27: ffffffc00a1c00c8
[    2.402613] x26: ffffffc00a2a6060 x25: 0000000000000006 x24: 0000000000000006
[    2.402620] x23: ffffffc009e7ec10 x22: ffffff80c1180910 x21: ffffffc00ac1f050
[    2.402627] x20: ffffff80c0a51300 x19: ffffff80c0a51300 x18: 0000000000000030
[    2.402633] x17: 28746572202c2930 x16: 3030303030286469 x15: ffffffffffffffff
[    2.402640] x14: 0000000000000000 x13: 29352d2874657220 x12: 2c29303030303030
[    2.402646] x11: 0000000000000001 x10: ffffff80c11ad1a8 x9 : ffffffc0088a6548
[    2.402653] x8 : ffffffc008afcf50 x7 : ffffff80c11ad1a8 x6 : ffffff80c11ad1a8
[    2.402660] x5 : ffffffc008afe8ec x4 : fffffffe03046b60 x3 : 0000000000000000
[    2.402666] x2 : ffffff80c0358000 x1 : 0000000000000000 x0 : 0000000000000001
[    2.402673] Call trace:
[    2.402677]  _regulator_put.part.0+0x158/0x160
[    2.402682]  regulator_bulk_free+0x64/0x8c
[    2.402687]  devm_regulator_bulk_release+0x20/0x30
[    2.402693]  devres_release_group+0x120/0x1f4
[    2.402698]  i2c_device_probe+0x138/0x350
[    2.402705]  really_probe+0xc4/0x3e0
[    2.402711]  __driver_probe_device+0x80/0x160
[    2.402717]  driver_probe_device+0x40/0x110
[    2.402722]  __driver_attach+0xec/0x1f0
[    2.402727]  bus_for_each_dev+0x74/0xd0
[    2.402732]  driver_attach+0x28/0x30
[    2.402737]  bus_add_driver+0x178/0x234
[    2.402742]  driver_register+0x7c/0x130
[    2.402747]  i2c_register_driver+0x4c/0xec
[    2.402753]  sensor_mod_init+0x20/0x28
[    2.402759]  do_one_initcall+0x48/0x250
[    2.402764]  kernel_init_freeable+0x298/0x304
[    2.402772]  kernel_init+0x28/0x12c
[    2.402776]  ret_from_fork+0x10/0x20

原因是执行了两次clk_disable_unprepare，需要把第二次重复的去掉：

static void __sc3336_power_off(struct sc3336 *sc3336)
{
        int ret;
        struct device *dev = &sc3336->client->dev;

        clk_disable_unprepare(sc3336->xvclk);
        if (sc3336->is_thunderboot) {
                if (sc3336->is_first_streamoff) {
                        sc3336->is_thunderboot = false;
                        sc3336->is_first_streamoff = false;
                } else {
                        return;
                }
        }

        if (!IS_ERR(sc3336->pwdn_gpio))
                gpiod_set_value_cansleep(sc3336->pwdn_gpio, 0);
        //clk_disable_unprepare(sc3336->xvclk);
        if (!IS_ERR(sc3336->reset_gpio))
                gpiod_set_value_cansleep(sc3336->reset_gpio, 0);
        if (!IS_ERR_OR_NULL(sc3336->pins_sleep)) {
                ret = pinctrl_select_state(sc3336->pinctrl,
                                           sc3336->pins_sleep);
                if (ret < 0)
                        dev_dbg(dev, "could not set pins\n");
        }
        regulator_bulk_disable(SC3336_NUM_SUPPLIES, sc3336->supplies);
}

sc3336p疑似也可能有类似问题