hwmon: (xgene-hwmon) Simplify PCC shared memory region handling

The PCC driver now handles mapping and unmapping of shared memory
areas as part of pcc_mbox_{request,free}_channel(). Without these before,
this xgene hwmon driver did handling of those mappings like several
other PCC mailbox client drivers.

There were redundant operations, leading to unnecessary code. Maintaining
the consistency across these driver was harder due to scattered handling
of shmem.

Just use the mapped shmem and remove all redundant operations from this
driver.

Cc: Jean Delvare <[e-mail]>
Cc: Guenter Roeck <[e-mail]>
Cc: [e-mail]
Signed-off-by: Sudeep Holla <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Guenter Roeck <[e-mail]>

drivers/hwmon/xgene-hwmon.c

···
 	struct device		*hwmon_dev;
 	bool			temp_critical_alarm;
 
-	phys_addr_t		comm_base_addr;
-	void			*pcc_comm_addr;
 	unsigned int		usecs_lat;
 };
 
···
 
 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;
+	struct acpi_pcct_shared_memory __iomem *generic_comm_base =
+							ctx->pcc_chan->shmem;
 	u32 *ptr = (void *)(generic_comm_base + 1);
 	int rc, i;
 	u16 val;
···
 static void xgene_hwmon_pcc_rx_cb(struct mbox_client *cl, void *msg)
 {
 	struct xgene_hwmon_dev *ctx = to_xgene_hwmon_dev(cl);
-	struct acpi_pcct_shared_memory *generic_comm_base = ctx->pcc_comm_addr;
+	struct acpi_pcct_shared_memory __iomem *generic_comm_base =
+							ctx->pcc_chan->shmem;
 	struct slimpro_resp_msg amsg;
 
 	/*
···
 	} else {
 		struct pcc_mbox_chan *pcc_chan;
 		const struct acpi_device_id *acpi_id;
-		int version;
 
 		acpi_id = acpi_match_device(pdev->dev.driver->acpi_match_table,
 					    &pdev->dev);
···
 			rc = -EINVAL;
 			goto out_mbox_free;
 		}
-
-		version = (int)acpi_id->driver_data;
 
 		if (device_property_read_u32(&pdev->dev, "pcc-channel",
 					     &ctx->mbox_idx)) {
···
 		if (!ctx->mbox_chan->mbox->txdone_irq) {
 			dev_err(&pdev->dev, "PCC IRQ not supported\n");
 			rc = -ENODEV;
-			goto out;
-		}
-
-		/*
-		 * This is the shared communication region
-		 * for the OS and Platform to communicate over.
-		 */
-		ctx->comm_base_addr = pcc_chan->shmem_base_addr;
-		if (ctx->comm_base_addr) {
-			if (version == XGENE_HWMON_V2)
-				ctx->pcc_comm_addr = (void __force *)devm_ioremap(&pdev->dev,
-								  ctx->comm_base_addr,
-								  pcc_chan->shmem_size);
-			else
-				ctx->pcc_comm_addr = devm_memremap(&pdev->dev,
-								   ctx->comm_base_addr,
-								   pcc_chan->shmem_size,
-								   MEMREMAP_WB);
-		} else {
-			dev_err(&pdev->dev, "Failed to get PCC comm region\n");
-			rc = -ENODEV;
-			goto out;
-		}
-
-		if (IS_ERR_OR_NULL(ctx->pcc_comm_addr)) {
-			dev_err(&pdev->dev,
-				"Failed to ioremap PCC comm region\n");
-			rc = -ENOMEM;
 			goto out;
 		}