scsi: ufs: ufs-pci: Correct check for RESET DSM

dsm_fns is a bitmap, and it is 0-indexed according to the check in
__intel_dsm function. But common initialization was checking it as if it
was 1-indexed. This patch corrects the discrepancy. This change won't break
any existing calls to the function, since before the change both bits 0 and
1 were checked and needed to be set.

Link: https://lore.kernel.org/r/20220728111748.v3.1.I22460c4f4a9ccf2c96c3f9bb392b409926d80b2f@changeid
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Daniil Lunev <dlunev@chromium.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/ufs/host/ufshcd-pci.c b/drivers/ufs/host/ufshcd-pci.c
index 24af1f3..1c91f43 100644 (file)
--- a/drivers/ufs/host/ufshcd-pci.c
+++ b/drivers/ufs/host/ufshcd-pci.c
@@ -24,7 +24,7 @@ struct ufs_host {
        void (*late_init)(struct ufs_hba *hba);
 };
 
-enum {
+enum intel_ufs_dsm_func_id {
        INTEL_DSM_FNS           =  0,
        INTEL_DSM_RESET         =  1,
 };
@@ -42,6 +42,15 @@ static const guid_t intel_dsm_guid =
        GUID_INIT(0x1A4832A0, 0x7D03, 0x43CA,
                  0xB0, 0x20, 0xF6, 0xDC, 0xD1, 0x2A, 0x19, 0x50);
 
+static bool __intel_dsm_supported(struct intel_host *host,
+                                 enum intel_ufs_dsm_func_id fn)
+{
+       return fn < 32 && fn >= 0 && (host->dsm_fns & (1u << fn));
+}
+
+#define INTEL_DSM_SUPPORTED(host, name) \
+       __intel_dsm_supported(host, INTEL_DSM_##name)
+
 static int __intel_dsm(struct intel_host *intel_host, struct device *dev,
                       unsigned int fn, u32 *result)
 {
@@ -71,7 +80,7 @@ out:
 static int intel_dsm(struct intel_host *intel_host, struct device *dev,
                     unsigned int fn, u32 *result)
 {
-       if (fn > 31 || !(intel_host->dsm_fns & (1 << fn)))
+       if (!__intel_dsm_supported(intel_host, fn))
                return -EOPNOTSUPP;
 
        return __intel_dsm(intel_host, dev, fn, result);
@@ -300,7 +309,7 @@ static int ufs_intel_device_reset(struct ufs_hba *hba)
 {
        struct intel_host *host = ufshcd_get_variant(hba);
 
-       if (host->dsm_fns & INTEL_DSM_RESET) {
+       if (INTEL_DSM_SUPPORTED(host, RESET)) {
                u32 result = 0;
                int err;
 
@@ -342,7 +351,7 @@ static int ufs_intel_common_init(struct ufs_hba *hba)
                return -ENOMEM;
        ufshcd_set_variant(hba, host);
        intel_dsm_init(host, hba->dev);
-       if (host->dsm_fns & INTEL_DSM_RESET) {
+       if (INTEL_DSM_SUPPORTED(host, RESET)) {
                if (hba->vops->device_reset)
                        hba->caps |= UFSHCD_CAP_DEEPSLEEP;
        } else {