From: Alvin Šipraga alsi@bang-olufsen.dk
Previously sent back in March, see here:
https://lore.kernel.org/dri-devel/20220319145939.978087-1-alvin@pqrs.dk/
No changes besides rebasing on today's drm-misc-fixes.
Alvin Šipraga (2): drm: bridge: adv7511: fix CEC power down control register offset drm: bridge: adv7511: unregister cec i2c device after cec adapter
drivers/gpu/drm/bridge/adv7511/adv7511.h | 5 +---- drivers/gpu/drm/bridge/adv7511/adv7511_cec.c | 4 ++-- drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 5 ++--- 3 files changed, 5 insertions(+), 9 deletions(-)
From: Alvin Šipraga alsi@bang-olufsen.dk
The ADV7511_REG_CEC_CTRL = 0xE2 register is part of the main register map - not the CEC register map. As such, we shouldn't apply an offset to the register address. Doing so will cause us to address a bogus register for chips with a CEC register map offset (e.g. ADV7533).
Fixes: 3b1b975003e4 ("drm: adv7511/33: add HDMI CEC support") Signed-off-by: Alvin Šipraga alsi@bang-olufsen.dk --- drivers/gpu/drm/bridge/adv7511/adv7511.h | 5 +---- drivers/gpu/drm/bridge/adv7511/adv7511_cec.c | 4 ++-- 2 files changed, 3 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511.h b/drivers/gpu/drm/bridge/adv7511/adv7511.h index 9e3bb8a8ee40..46ae6c0d9aa5 100644 --- a/drivers/gpu/drm/bridge/adv7511/adv7511.h +++ b/drivers/gpu/drm/bridge/adv7511/adv7511.h @@ -406,10 +406,7 @@ void adv7511_cec_irq_process(struct adv7511 *adv7511, unsigned int irq1); #else static inline int adv7511_cec_init(struct device *dev, struct adv7511 *adv7511) { - unsigned int offset = adv7511->type == ADV7533 ? - ADV7533_REG_CEC_OFFSET : 0; - - regmap_write(adv7511->regmap, ADV7511_REG_CEC_CTRL + offset, + regmap_write(adv7511->regmap, ADV7511_REG_CEC_CTRL, ADV7511_CEC_CTRL_POWER_DOWN); return 0; } diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_cec.c b/drivers/gpu/drm/bridge/adv7511/adv7511_cec.c index 399f625a50c8..6d067fa54bea 100644 --- a/drivers/gpu/drm/bridge/adv7511/adv7511_cec.c +++ b/drivers/gpu/drm/bridge/adv7511/adv7511_cec.c @@ -347,7 +347,7 @@ int adv7511_cec_init(struct device *dev, struct adv7511 *adv7511) goto err_cec_alloc; }
- regmap_write(adv7511->regmap, ADV7511_REG_CEC_CTRL + offset, 0); + regmap_write(adv7511->regmap, ADV7511_REG_CEC_CTRL, 0); /* cec soft reset */ regmap_write(adv7511->regmap_cec, ADV7511_REG_CEC_SOFT_RESET + offset, 0x01); @@ -374,7 +374,7 @@ int adv7511_cec_init(struct device *dev, struct adv7511 *adv7511) dev_info(dev, "Initializing CEC failed with error %d, disabling CEC\n", ret); err_cec_parse_dt: - regmap_write(adv7511->regmap, ADV7511_REG_CEC_CTRL + offset, + regmap_write(adv7511->regmap, ADV7511_REG_CEC_CTRL, ADV7511_CEC_CTRL_POWER_DOWN); return ret == -EPROBE_DEFER ? ret : 0; }
From: Alvin Šipraga alsi@bang-olufsen.dk
cec_unregister_adapter() assumes that the underlying adapter ops are callable. For example, if the CEC adapter currently has a valid physical address, then the unregistration procedure will invalidate the physical address by setting it to f.f.f.f. Whence the following kernel oops observed after removing the adv7511 module:
Unable to handle kernel execution of user memory at virtual address 0000000000000000 Internal error: Oops: 86000004 [#1] PREEMPT_RT SMP Call trace: 0x0 adv7511_cec_adap_log_addr+0x1ac/0x1c8 [adv7511] cec_adap_unconfigure+0x44/0x90 [cec] __cec_s_phys_addr.part.0+0x68/0x230 [cec] __cec_s_phys_addr+0x40/0x50 [cec] cec_unregister_adapter+0xb4/0x118 [cec] adv7511_remove+0x60/0x90 [adv7511] i2c_device_remove+0x34/0xe0 device_release_driver_internal+0x114/0x1f0 driver_detach+0x54/0xe0 bus_remove_driver+0x60/0xd8 driver_unregister+0x34/0x60 i2c_del_driver+0x2c/0x68 adv7511_exit+0x1c/0x67c [adv7511] __arm64_sys_delete_module+0x154/0x288 invoke_syscall+0x48/0x100 el0_svc_common.constprop.0+0x48/0xe8 do_el0_svc+0x28/0x88 el0_svc+0x1c/0x50 el0t_64_sync_handler+0xa8/0xb0 el0t_64_sync+0x15c/0x160 Code: bad PC value ---[ end trace 0000000000000000 ]---
Protect against this scenario by unregistering i2c_cec after unregistering the CEC adapter. Duly disable the CEC clock afterwards too.
Fixes: 3b1b975003e4 ("drm: adv7511/33: add HDMI CEC support") Signed-off-by: Alvin Šipraga alsi@bang-olufsen.dk --- drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c index 5bb9300040dd..023c0ad132e0 100644 --- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c +++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c @@ -1339,9 +1339,6 @@ static int adv7511_remove(struct i2c_client *i2c) { struct adv7511 *adv7511 = i2c_get_clientdata(i2c);
- i2c_unregister_device(adv7511->i2c_cec); - clk_disable_unprepare(adv7511->cec_clk); - adv7511_uninit_regulators(adv7511);
drm_bridge_remove(&adv7511->bridge); @@ -1349,6 +1346,8 @@ static int adv7511_remove(struct i2c_client *i2c) adv7511_audio_exit(adv7511);
cec_unregister_adapter(adv7511->cec_adap); + i2c_unregister_device(adv7511->i2c_cec); + clk_disable_unprepare(adv7511->cec_clk);
i2c_unregister_device(adv7511->i2c_packet); i2c_unregister_device(adv7511->i2c_edid);
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