Re: [PATCH] qmi: radio-settings: Do not unconditionally try to enable unsupported modes

[Denis Kenzior <denkenz@gmail.com>]

Hi Ivo,

On 12/7/24 11:20 AM, Ivaylo Dimitrov wrote:
> At least the modem in Motorola Droid 4 errors out if anything else but GSM
> and UMTS bits are set when selecting preferred mode. That happens if 'any'
> mode is set.
> 
> Fix that by querying supported modes and passing only those for 'any' mode.
> ---
>   drivers/qmimodem/radio-settings.c | 97 +++++++++++++++++++++++++++++--
>   drivers/qmimodem/util.h           | 19 +++---
>   2 files changed, 104 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/qmimodem/radio-settings.c b/drivers/qmimodem/radio-settings.c
> index cf0b747e..b62a87d0 100644
> --- a/drivers/qmimodem/radio-settings.c
> +++ b/drivers/qmimodem/radio-settings.c

<snip>

> @@ -136,14 +142,91 @@ static void qmi_set_rat_mode(struct ofono_radio_settings *rs, unsigned int mode,
>   	l_free(cbd);
>   }
>   
> +static void get_rat_mode_any_cb(struct qmi_result *result, void *user_data)
> +{
> +	struct rat_mode_any_data *data = user_data;
> +	struct cb_data *cbd = &data->cbd;
> +	struct ofono_radio_settings *rs = cbd->user;
> +	struct settings_data *rsd = ofono_radio_settings_get_data(rs);
> +	const struct qmi_dms_device_caps *caps;
> +	uint16_t len;
> +	uint8_t i;
> +
> +	DBG("");
> +
> +	if (qmi_result_set_error(result, NULL))
> +		goto error;
> +
> +	caps = qmi_result_get(result, QMI_DMS_RESULT_DEVICE_CAPS, &len);
> +	if (!caps)
> +		goto error;
> +
> +	for (i = 0; i < caps->radio_if_count; i++) {
> +		switch (caps->radio_if[i]) {
> +		case QMI_DMS_RADIO_IF_GSM:
> +			rsd->rat_mode_any |= QMI_NAS_RAT_MODE_PREF_GSM;
> +			break;
> +		case QMI_DMS_RADIO_IF_UMTS:
> +			rsd->rat_mode_any |= QMI_NAS_RAT_MODE_PREF_UMTS;
> +			break;
> +		case QMI_DMS_RADIO_IF_LTE:
> +			rsd->rat_mode_any |= QMI_NAS_RAT_MODE_PREF_LTE;
> +			break;
> +		}
> +	}

This looks like copy-paste of get_caps_cb.  Lets avoid that by invoking 
QMI_DMS_GET_CAPS during probe().  See below.

> +
> +error:
> +	/* last resort */
> +	if (rsd->rat_mode_any == 0)
> +		rsd->rat_mode_any = QMI_NAS_RAT_MODE_PREF_ANY;
> +
> +	_set_rat_mode(rs, data->mode, cbd->cb, cbd->data);
> +}
> +
> +static bool get_rat_mode_any(struct ofono_radio_settings *rs, unsigned int mode,
> +			ofono_radio_settings_rat_mode_set_cb_t cb,
> +			void *user_data)
> +{
> +	struct settings_data *rsd = ofono_radio_settings_get_data(rs);
> +	struct rat_mode_any_data *data = l_new(struct rat_mode_any_data, 1);
> +	struct cb_data *cbd = cb_data_init(&data->cbd, cb, user_data);
> +
> +	if (!rsd->dms)
> +		goto error;
> +
> +	cbd->user = rs;
> +	data->mode = mode;
> +
> +	if (qmi_service_send(rsd->dms, QMI_DMS_GET_CAPS, NULL,
> +					get_rat_mode_any_cb, data, l_free) > 0)
> +		return true;
> +
> +error:
> +	l_free(data);
> +	rsd->rat_mode_any = QMI_NAS_RAT_MODE_PREF_ANY;
> +	return false;
> +}
> +
> +static void qmi_set_rat_mode(struct ofono_radio_settings *rs, unsigned int mode,
> +			ofono_radio_settings_rat_mode_set_cb_t cb,
> +			void *user_data)
> +{
> +	struct settings_data *rsd = ofono_radio_settings_get_data(rs);
> +
> +	if (rsd->rat_mode_any || !get_rat_mode_any(rs, mode, cb, user_data))

So your intent here is to query the radio capabilities first if they haven't 
been queried before?  If so, then the typical pattern is to do this during 
probe(), before calling ofono_radio_settings_register().  See qmimodem/lte.c for 
an example.

> +		_set_rat_mode(rs, mode, cb, user_data);
> +}
> +
>   static void get_caps_cb(struct qmi_result *result, void *user_data)
>   {
>   	struct cb_data *cbd = user_data;
> +	struct ofono_radio_settings *rs = cbd->user;
> +	struct settings_data *rsd = ofono_radio_settings_get_data(rs);
>   	ofono_radio_settings_available_rats_query_cb_t cb = cbd->cb;
>   	const struct qmi_dms_device_caps *caps;
> -	unsigned int available_rats;
>   	uint16_t len;
>   	uint8_t i;
> +	unsigned int available_rats;

Why is 'available_rats' being moved?

>   
>   	DBG("");
>   
> @@ -155,16 +238,20 @@ static void get_caps_cb(struct qmi_result *result, void *user_data)
>   		goto error;
>   
>   	available_rats = 0;
> +
>   	for (i = 0; i < caps->radio_if_count; i++) {
>   		switch (caps->radio_if[i]) {
>   		case QMI_DMS_RADIO_IF_GSM:
>   			available_rats |= OFONO_RADIO_ACCESS_MODE_GSM;
> +			rsd->rat_mode_any |= QMI_NAS_RAT_MODE_PREF_GSM;
>   			break;
>   		case QMI_DMS_RADIO_IF_UMTS:
>   			available_rats |= OFONO_RADIO_ACCESS_MODE_UMTS;
> +			rsd->rat_mode_any |= QMI_NAS_RAT_MODE_PREF_UMTS;
>   			break;
>   		case QMI_DMS_RADIO_IF_LTE:
>   			available_rats |= OFONO_RADIO_ACCESS_MODE_LTE;
> +			rsd->rat_mode_any |= QMI_NAS_RAT_MODE_PREF_LTE;
>   			break;
>   		}
>   	}

Wouldn't it be easier to simply do
rsd->rat_mode_any = available_rats?

> diff --git a/drivers/qmimodem/util.h b/drivers/qmimodem/util.h
> index 58bf4f98..14d4d865 100644
> --- a/drivers/qmimodem/util.h
> +++ b/drivers/qmimodem/util.h
> @@ -14,17 +14,20 @@ struct cb_data {
>   	int ref;
>   };
>   
> -static inline struct cb_data *cb_data_new(void *cb, void *data)
> +static inline struct cb_data *cb_data_init(struct cb_data *cbd, void *cb,
> +						void *data)
>   {
> -	struct cb_data *ret;
> +	cbd->cb = cb;
> +	cbd->data = data;
> +	cbd->user = NULL;
> +	cbd->ref = 1;
>   
> -	ret = l_new(struct cb_data, 1);
> -	ret->cb = cb;
> -	ret->data = data;
> -	ret->user = NULL;
> -	ret->ref = 1;
> +	return cbd;
> +}
>   
> -	return ret;
> +static inline struct cb_data *cb_data_new(void *cb, void *data)
> +{
> +	return cb_data_init(l_new(struct cb_data, 1), cb, data);
>   }
>   
>   static inline struct cb_data *cb_data_ref(struct cb_data *cbd)

You likely don't need any of this...

Regards,
-Denis