[PATCH v2] hwmon: xgene: Support hwmon v2

[Hoan Tran <hotran@apm.com>]

This patch supports xgene-hwmon v2 which uses the non-cachable memory
as the PCC shared memory.

Signed-off-by: Hoan Tran <hotran@apm.com>
---

v2
 - Map PCC shared mem by ioremap() in case hwmon is v2

 drivers/hwmon/xgene-hwmon.c | 52 +++++++++++++++++++++++++++++++++++----------
 1 file changed, 41 insertions(+), 11 deletions(-)

diff --git a/drivers/hwmon/xgene-hwmon.c b/drivers/hwmon/xgene-hwmon.c
index 9c0dbb8..52be7cd 100644
--- a/drivers/hwmon/xgene-hwmon.c
+++ b/drivers/hwmon/xgene-hwmon.c
@@ -91,6 +91,11 @@
 #define to_xgene_hwmon_dev(cl)		\
 	container_of(cl, struct xgene_hwmon_dev, mbox_client)
 
+enum xgene_hwmon_version {
+	XGENE_HWMON_V1 = 0,
+	XGENE_HWMON_V2 = 1,
+};
+
 struct slimpro_resp_msg {
 	u32 msg;
 	u32 param1;
@@ -99,6 +104,7 @@ struct slimpro_resp_msg {
 
 struct xgene_hwmon_dev {
 	struct device		*dev;
+	int			version;
 	struct mbox_chan	*mbox_chan;
 	struct mbox_client	mbox_client;
 	int			mbox_idx;
@@ -135,6 +141,15 @@ static u16 xgene_word_tst_and_clr(u16 *addr, u16 mask)
 	return ret;
 }
 
+static void *xgene_pcc_ioremap(struct xgene_hwmon_dev *ctx,
+			       phys_addr_t phys, size_t size)
+{
+	if (ctx->version == XGENE_HWMON_V2)
+		return (void __force *)ioremap(phys, size);
+
+	return memremap(phys, size, MEMREMAP_WB);
+}
+
 static int xgene_hwmon_pcc_rd(struct xgene_hwmon_dev *ctx, u32 *msg)
 {
 	struct acpi_pcct_shared_memory *generic_comm_base = ctx->pcc_comm_addr;
@@ -609,6 +624,15 @@ static void xgene_hwmon_tx_done(struct mbox_client *cl, void *msg, int ret)
 	}
 }
 
+#ifdef CONFIG_ACPI
+static const struct acpi_device_id xgene_hwmon_acpi_match[] = {
+	{"APMC0D29", XGENE_HWMON_V1},
+	{"APMC0D8A", XGENE_HWMON_V2},
+	{},
+};
+MODULE_DEVICE_TABLE(acpi, xgene_hwmon_acpi_match);
+#endif
+
 static int xgene_hwmon_probe(struct platform_device *pdev)
 {
 	struct xgene_hwmon_dev *ctx;
@@ -623,6 +647,20 @@ static int xgene_hwmon_probe(struct platform_device *pdev)
 	platform_set_drvdata(pdev, ctx);
 	cl = &ctx->mbox_client;
 
+#ifdef CONFIG_ACPI
+	ctx->version = -EINVAL;
+	if (ACPI_COMPANION(&pdev->dev)) {
+		const struct acpi_device_id *acpi_id;
+
+		acpi_id = acpi_match_device(xgene_hwmon_acpi_match, &pdev->dev);
+		if (acpi_id)
+			ctx->version = (int)acpi_id->driver_data;
+	}
+
+	if (ctx->version < 0)
+		return -ENODEV;
+#endif
+
 	spin_lock_init(&ctx->kfifo_lock);
 	mutex_init(&ctx->rd_mutex);
 
@@ -690,9 +728,9 @@ static int xgene_hwmon_probe(struct platform_device *pdev)
 		 */
 		ctx->comm_base_addr = cppc_ss->base_address;
 		if (ctx->comm_base_addr) {
-			ctx->pcc_comm_addr = memremap(ctx->comm_base_addr,
-							cppc_ss->length,
-							MEMREMAP_WB);
+			ctx->pcc_comm_addr = xgene_pcc_ioremap(ctx,
+						ctx->comm_base_addr,
+						cppc_ss->length);
 		} else {
 			dev_err(&pdev->dev, "Failed to get PCC comm region\n");
 			rc = -ENODEV;
@@ -758,14 +796,6 @@ static int xgene_hwmon_remove(struct platform_device *pdev)
 	return 0;
 }
 
-#ifdef CONFIG_ACPI
-static const struct acpi_device_id xgene_hwmon_acpi_match[] = {
-	{"APMC0D29", 0},
-	{},
-};
-MODULE_DEVICE_TABLE(acpi, xgene_hwmon_acpi_match);
-#endif
-
 static const struct of_device_id xgene_hwmon_of_match[] = {
 	{.compatible = "apm,xgene-slimpro-hwmon"},
 	{}
-- 
1.9.1