diff options
Diffstat (limited to 'drivers/ufs/host/ufshcd-pltfrm.c')
| -rw-r--r-- | drivers/ufs/host/ufshcd-pltfrm.c | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/drivers/ufs/host/ufshcd-pltfrm.c b/drivers/ufs/host/ufshcd-pltfrm.c index ffe5d1d2b215..c2dafb583cf5 100644 --- a/drivers/ufs/host/ufshcd-pltfrm.c +++ b/drivers/ufs/host/ufshcd-pltfrm.c @@ -430,6 +430,39 @@ int ufshcd_negotiate_pwr_params(const struct ufs_host_params *host_params, } EXPORT_SYMBOL_GPL(ufshcd_negotiate_pwr_params); +/** + * ufshcd_parse_gear_limits - Parse DT-based gear and rate limits for UFS + * @hba: Pointer to UFS host bus adapter instance + * @host_params: Pointer to UFS host parameters structure to be updated + * + * This function reads optional device tree properties to apply + * platform-specific constraints. + * + * "limit-hs-gear": Specifies the max HS gear. + * "limit-gear-rate": Specifies the max High-Speed rate. + */ +void ufshcd_parse_gear_limits(struct ufs_hba *hba, struct ufs_host_params *host_params) +{ + struct device_node *np = hba->dev->of_node; + u32 hs_gear; + const char *hs_rate; + + if (!of_property_read_u32(np, "limit-hs-gear", &hs_gear)) { + host_params->hs_tx_gear = hs_gear; + host_params->hs_rx_gear = hs_gear; + } + + if (!of_property_read_string(np, "limit-gear-rate", &hs_rate)) { + if (!strcmp(hs_rate, "rate-a")) + host_params->hs_rate = PA_HS_MODE_A; + else if (!strcmp(hs_rate, "rate-b")) + host_params->hs_rate = PA_HS_MODE_B; + else + dev_warn(hba->dev, "Invalid rate: %s\n", hs_rate); + } +} +EXPORT_SYMBOL_GPL(ufshcd_parse_gear_limits); + void ufshcd_init_host_params(struct ufs_host_params *host_params) { *host_params = (struct ufs_host_params){ |