spmi: msm: introduce SPMI_CHANNEL_VALID flag

Introduce the SPMI_CHANNEL_VALID flag so we can check if
a mapping exists for a SPMI command.

Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Tested-by: caleb.connolly@linaro.org # sdm845
Link: https://lore.kernel.org/r/20250328-topic-sm8x50-spmi-fix-v1-3-a7548d3aef0d@linaro.org
Signed-off-by: Caleb Connolly <caleb.connolly@linaro.org>

diff --git a/drivers/spmi/spmi-msm.c b/drivers/spmi/spmi-msm.c
index 9b2be1c..ee3feaf 100644 (file)
--- a/drivers/spmi/spmi-msm.c
+++ b/drivers/spmi/spmi-msm.c
@@ -63,6 +63,7 @@ DECLARE_GLOBAL_DATA_PTR;
 #define SPMI_MAX_PERIPH 256
 
 #define SPMI_CHANNEL_READ_ONLY BIT(31)
+#define SPMI_CHANNEL_VALID     BIT(30)
 #define SPMI_CHANNEL_MASK      0xffff
 
 enum arb_ver {
@@ -117,6 +118,8 @@ static int msm_spmi_write(struct udevice *dev, int usid, int pid, int off,
                return -EIO;
        if (pid >= SPMI_MAX_PERIPH)
                return -EIO;
+       if (!(priv->channel_map[usid][pid] & SPMI_CHANNEL_VALID))
+               return -EINVAL;
        if (priv->channel_map[usid][pid] & SPMI_CHANNEL_READ_ONLY)
                return -EPERM;
 
@@ -186,6 +189,8 @@ static int msm_spmi_read(struct udevice *dev, int usid, int pid, int off)
                return -EIO;
        if (pid >= SPMI_MAX_PERIPH)
                return -EIO;
+       if (!(priv->channel_map[usid][pid] & SPMI_CHANNEL_VALID))
+               return -EINVAL;
 
        channel = priv->channel_map[usid][pid] & SPMI_CHANNEL_MASK;
 
@@ -256,7 +261,7 @@ static void msm_spmi_channel_map_v5(struct msm_spmi_priv *priv, unsigned int i,
        uint32_t cnfg = readl(priv->spmi_cnfg + ARB_CHANNEL_OFFSET(i));
        uint8_t owner = SPMI_OWNERSHIP_PERIPH2OWNER(cnfg);
 
-       priv->channel_map[slave_id][pid] = i;
+       priv->channel_map[slave_id][pid] = i | SPMI_CHANNEL_VALID;
        if (owner != priv->owner)
                priv->channel_map[slave_id][pid] |= SPMI_CHANNEL_READ_ONLY;
 }
@@ -319,7 +324,7 @@ static int msm_spmi_probe(struct udevice *dev)
                switch (priv->arb_ver) {
                case V2:
                case V3:
-                       priv->channel_map[slave_id][pid] = i;
+                       priv->channel_map[slave_id][pid] = i | SPMI_CHANNEL_VALID;
                        break;
 
                case V5: