CEC interrupt status/mask and logical address registers will be reset when device enter suspend. It will cause cec fail to work after device resume. Add CEC suspend/resume functions, reinitialize logical address registers and restore interrupt status/mask registers after resume. Signed-off-by: Sandor Yu <Sandor.yu@xxxxxxx> --- drivers/gpu/drm/bridge/synopsys/dw-hdmi-cec.c | 37 +++++++++++++++++++ 1 file changed, 37 insertions(+) diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi-cec.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi-cec.c index 9389ce526eb13..be21c11de1f2a 100644 --- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi-cec.c +++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi-cec.c @@ -62,6 +62,10 @@ struct dw_hdmi_cec { bool rx_done; struct cec_notifier *notify; int irq; + + u8 regs_polarity; + u8 regs_mask; + u8 regs_mute_stat0; }; static void dw_hdmi_write(struct dw_hdmi_cec *cec, u8 val, int offset) @@ -304,11 +308,44 @@ static void dw_hdmi_cec_remove(struct platform_device *pdev) cec_unregister_adapter(cec->adap); } +static int __maybe_unused dw_hdmi_cec_resume(struct device *dev) +{ + struct dw_hdmi_cec *cec = dev_get_drvdata(dev); + + /* Restore logical address */ + dw_hdmi_write(cec, cec->addresses & 255, HDMI_CEC_ADDR_L); + dw_hdmi_write(cec, cec->addresses >> 8, HDMI_CEC_ADDR_H); + + /* Restore interrupt status/mask registers */ + dw_hdmi_write(cec, cec->regs_polarity, HDMI_CEC_POLARITY); + dw_hdmi_write(cec, cec->regs_mask, HDMI_CEC_MASK); + dw_hdmi_write(cec, cec->regs_mute_stat0, HDMI_IH_MUTE_CEC_STAT0); + + return 0; +} + +static int __maybe_unused dw_hdmi_cec_suspend(struct device *dev) +{ + struct dw_hdmi_cec *cec = dev_get_drvdata(dev); + + /* store interrupt status/mask registers */ + cec->regs_polarity = dw_hdmi_read(cec, HDMI_CEC_POLARITY); + cec->regs_mask = dw_hdmi_read(cec, HDMI_CEC_MASK); + cec->regs_mute_stat0 = dw_hdmi_read(cec, HDMI_IH_MUTE_CEC_STAT0); + + return 0; +} + +static const struct dev_pm_ops dw_hdmi_cec_pm = { + SET_SYSTEM_SLEEP_PM_OPS(dw_hdmi_cec_suspend, dw_hdmi_cec_resume) +}; + static struct platform_driver dw_hdmi_cec_driver = { .probe = dw_hdmi_cec_probe, .remove_new = dw_hdmi_cec_remove, .driver = { .name = "dw-hdmi-cec", + .pm = &dw_hdmi_cec_pm, }, }; module_platform_driver(dw_hdmi_cec_driver); -- 2.34.1