On Mon, Jun 03, 2019 at 10:05:45AM -0700, Ajay Gupta wrote:
> From: Ajay Gupta <ajayg@xxxxxxxxxx>
>
> Cypress USB Type-C CCGx controller firmware version 3.1.10
> (which is being used in many NVIDIA GPU cards) has known issue of
> not triggering interrupt when a USB device is hot plugged to runtime
> resume the controller. If any GPU card gets latest kernel with runtime
> pm support but does not get latest fixed firmware then also it should
> continue to work and therefore a workaround is required to check for
> any connector change event.
>
> The workaround is that i2c bus driver will call pm_request_resume()
> to runtime resume ucsi_ccg driver. CCG driver will call the ISR
> for any connector change event for NVIDIA GPU card and only if it has
> old CCG firmware with the known issue.
>
> Signed-off-by: Ajay Gupta <ajayg@xxxxxxxxxx>
Acked-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
> ---
> Changes from v3->v4: None
>
> drivers/usb/typec/ucsi/ucsi_ccg.c | 80 +++++++++++++++++++++++++++++--
> 1 file changed, 76 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/usb/typec/ucsi/ucsi_ccg.c b/drivers/usb/typec/ucsi/ucsi_ccg.c
> index b15bc6c29c46..a5b81c011148 100644
> --- a/drivers/usb/typec/ucsi/ucsi_ccg.c
> +++ b/drivers/usb/typec/ucsi/ucsi_ccg.c
> @@ -109,12 +109,21 @@ struct version_format {
> __le16 build;
> u8 patch;
> u8 ver;
> +#define CCG_VERSION_PATCH(x) ((x) << 16)
> +#define CCG_VERSION(x) ((x) << 24)
> #define CCG_VERSION_MIN_SHIFT (0)
> #define CCG_VERSION_MIN_MASK (0xf << CCG_VERSION_MIN_SHIFT)
> #define CCG_VERSION_MAJ_SHIFT (4)
> #define CCG_VERSION_MAJ_MASK (0xf << CCG_VERSION_MAJ_SHIFT)
> } __packed;
>
> +/*
> + * Firmware version 3.1.10 or earlier, built for NVIDIA has known issue
> + * of missing interrupt when a device is connected for runtime resume
> + */
> +#define CCG_FW_BUILD_NVIDIA (('n' << 8) | 'v')
> +#define CCG_OLD_FW_VERSION (CCG_VERSION(0x31) | CCG_VERSION_PATCH(10))
> +
> struct version_info {
> struct version_format base;
> struct version_format app;
> @@ -172,6 +181,7 @@ struct ucsi_ccg {
> struct ccg_dev_info info;
> /* version info for boot, primary and secondary */
> struct version_info version[FW2 + 1];
> + u32 fw_version;
> /* CCG HPI communication flags */
> unsigned long flags;
> #define RESET_PENDING 0
> @@ -185,6 +195,8 @@ struct ucsi_ccg {
>
> /* fw build with vendor information */
> u16 fw_build;
> + bool run_isr; /* flag to call ISR routine during resume */
> + struct work_struct pm_work;
> };
>
> static int ccg_read(struct ucsi_ccg *uc, u16 rab, u8 *data, u32 len)
> @@ -212,6 +224,18 @@ static int ccg_read(struct ucsi_ccg *uc, u16 rab, u8 *data, u32 len)
> if (quirks && quirks->max_read_len)
> max_read_len = quirks->max_read_len;
>
> + if (uc->fw_build == CCG_FW_BUILD_NVIDIA &&
> + uc->fw_version <= CCG_OLD_FW_VERSION) {
> + mutex_lock(&uc->lock);
> + /*
> + * Do not schedule pm_work to run ISR in
> + * ucsi_ccg_runtime_resume() after pm_runtime_get_sync()
> + * since we are already in ISR path.
> + */
> + uc->run_isr = false;
> + mutex_unlock(&uc->lock);
> + }
> +
> pm_runtime_get_sync(uc->dev);
> while (rem_len > 0) {
> msgs[1].buf = &data[len - rem_len];
> @@ -254,6 +278,18 @@ static int ccg_write(struct ucsi_ccg *uc, u16 rab, u8 *data, u32 len)
> msgs[0].len = len + sizeof(rab);
> msgs[0].buf = buf;
>
> + if (uc->fw_build == CCG_FW_BUILD_NVIDIA &&
> + uc->fw_version <= CCG_OLD_FW_VERSION) {
> + mutex_lock(&uc->lock);
> + /*
> + * Do not schedule pm_work to run ISR in
> + * ucsi_ccg_runtime_resume() after pm_runtime_get_sync()
> + * since we are already in ISR path.
> + */
> + uc->run_isr = false;
> + mutex_unlock(&uc->lock);
> + }
> +
> pm_runtime_get_sync(uc->dev);
> status = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
> if (status < 0) {
> @@ -383,6 +419,13 @@ static irqreturn_t ccg_irq_handler(int irq, void *data)
> return IRQ_HANDLED;
> }
>
> +static void ccg_pm_workaround_work(struct work_struct *pm_work)
> +{
> + struct ucsi_ccg *uc = container_of(pm_work, struct ucsi_ccg, pm_work);
> +
> + ucsi_notify(uc->ucsi);
> +}
> +
> static int get_fw_info(struct ucsi_ccg *uc)
> {
> int err;
> @@ -392,6 +435,9 @@ static int get_fw_info(struct ucsi_ccg *uc)
> if (err < 0)
> return err;
>
> + uc->fw_version = CCG_VERSION(uc->version[FW2].app.ver) |
> + CCG_VERSION_PATCH(uc->version[FW2].app.patch);
> +
> err = ccg_read(uc, CCGX_RAB_DEVICE_MODE, (u8 *)(&uc->info),
> sizeof(uc->info));
> if (err < 0)
> @@ -740,11 +786,12 @@ static bool ccg_check_fw_version(struct ucsi_ccg *uc, const char *fw_name,
> }
>
> /* compare input version with FWCT version */
> - cur_version = le16_to_cpu(app->build) | app->patch << 16 |
> - app->ver << 24;
> + cur_version = le16_to_cpu(app->build) | CCG_VERSION_PATCH(app->patch) |
> + CCG_VERSION(app->ver);
>
> - new_version = le16_to_cpu(fw_cfg.app.build) | fw_cfg.app.patch << 16 |
> - fw_cfg.app.ver << 24;
> + new_version = le16_to_cpu(fw_cfg.app.build) |
> + CCG_VERSION_PATCH(fw_cfg.app.patch) |
> + CCG_VERSION(fw_cfg.app.ver);
>
> if (!ccg_check_vendor_version(uc, app, &fw_cfg))
> goto out_release_firmware;
> @@ -1084,8 +1131,10 @@ static int ucsi_ccg_probe(struct i2c_client *client,
> uc->ppm.sync = ucsi_ccg_sync;
> uc->dev = dev;
> uc->client = client;
> + uc->run_isr = true;
> mutex_init(&uc->lock);
> INIT_WORK(&uc->work, ccg_update_firmware);
> + INIT_WORK(&uc->pm_work, ccg_pm_workaround_work);
>
> /* Only fail FW flashing when FW build information is not provided */
> status = device_property_read_u16(dev, "ccgx,firmware-build",
> @@ -1153,6 +1202,7 @@ static int ucsi_ccg_remove(struct i2c_client *client)
> {
> struct ucsi_ccg *uc = i2c_get_clientdata(client);
>
> + cancel_work_sync(&uc->pm_work);
> cancel_work_sync(&uc->work);
> ucsi_unregister_ppm(uc->ucsi);
> pm_runtime_disable(uc->dev);
> @@ -1183,6 +1233,28 @@ static int ucsi_ccg_runtime_suspend(struct device *dev)
>
> static int ucsi_ccg_runtime_resume(struct device *dev)
> {
> + struct i2c_client *client = to_i2c_client(dev);
> + struct ucsi_ccg *uc = i2c_get_clientdata(client);
> + bool schedule = true;
> +
> + /*
> + * Firmware version 3.1.10 or earlier, built for NVIDIA has known issue
> + * of missing interrupt when a device is connected for runtime resume.
> + * Schedule a work to call ISR as a workaround.
> + */
> + if (uc->fw_build == CCG_FW_BUILD_NVIDIA &&
> + uc->fw_version <= CCG_OLD_FW_VERSION) {
> + mutex_lock(&uc->lock);
> + if (!uc->run_isr) {
> + uc->run_isr = true;
> + schedule = false;
> + }
> + mutex_unlock(&uc->lock);
> +
> + if (schedule)
> + schedule_work(&uc->pm_work);
> + }
> +
> return 0;
> }
>
> --
> 2.17.1
thanks,
--
heikki
