[PATCH 1/4] spmi: msm: use real number of channels for v5 & v7

[Neil Armstrong]

The SPMI_MAX_CHANNELS_Vx are only the maximum channels supported
by the controller, but the real number of channels mapped on this
system can be read from a register, so take this info.

This allows no to overlap on the second controller present on
the V7 SPMI arbiter, otherwise we would also parse the mapping
of the second SPMI bus and we would bet the wrong IDs.

Signed-off-by: Neil Armstrong <neil.armstrong at linaro.org>
---
 drivers/spmi/spmi-msm.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/spmi/spmi-msm.c b/drivers/spmi/spmi-msm.c
index 5cc5a9e654c8371d71386384654e9429ed96b05f..08be4517df189f320302e97334a371d370b36440 100644
--- a/drivers/spmi/spmi-msm.c
+++ b/drivers/spmi/spmi-msm.c
@@ -24,6 +24,9 @@ DECLARE_GLOBAL_DATA_PTR;
 #define PMIC_ARB_VERSION_V5_MIN 0x50000000
 #define PMIC_ARB_VERSION_V7_MIN	0x70000000
 
+#define PMIC_ARB_FEATURES		0x0004
+#define PMIC_ARB_FEATURES_PERIPH_MASK	GENMASK(10, 0)
+
 #define APID_MAP_OFFSET_V1_V2_V3 (0x800)
 #define APID_MAP_OFFSET_V5 (0x900)
 #define APID_MAP_OFFSET_V7 (0x2000)
@@ -271,13 +274,17 @@ static int msm_spmi_probe(struct udevice *dev)
 	} else if (hw_ver < PMIC_ARB_VERSION_V7_MIN) {
 		priv->arb_ver = V5;
 		priv->arb_chnl = core_addr + APID_MAP_OFFSET_V5;
-		priv->max_channels = SPMI_MAX_CHANNELS_V5;
+		priv->max_channels = min_t(u32, readl(core_addr + PMIC_ARB_FEATURES) &
+						PMIC_ARB_FEATURES_PERIPH_MASK,
+					   SPMI_MAX_CHANNELS_V5);
 		priv->spmi_cnfg = dev_read_addr_name(dev, "cnfg");
 	} else {
 		/* TOFIX: handle second bus */
 		priv->arb_ver = V7;
 		priv->arb_chnl = core_addr + APID_MAP_OFFSET_V7;
-		priv->max_channels = SPMI_MAX_CHANNELS_V7;
+		priv->max_channels = min_t(u32, readl(core_addr + PMIC_ARB_FEATURES) &
+						PMIC_ARB_FEATURES_PERIPH_MASK,
+					   SPMI_MAX_CHANNELS_V7);
 		priv->spmi_cnfg = dev_read_addr_name(dev, "cnfg");
 	}
 

-- 
2.34.1