linux-t2-patches/3002-applesmc-make-io-port-base-addr-dynamic.patch

From 713e78b8dbb8adb92d4ee09ea11e726b05577689 Mon Sep 17 00:00:00 2001
From: Paul Pawlowski <paul@mrarm.io>
Date: Sun, 17 Nov 2019 23:11:56 +0100
Subject: [PATCH 2/6] applesmc: make io port base addr dynamic

This change makes the port base runtime configurable.
The reason why this change is made is so that when we switch to an
acpi_device we can resolve the port base addr from ACPI.

This change is not strictly required for T2 support - the base
address is still 0x300 on T2 Macs.

Signed-off-by: Aun-Ali Zaidi <admin@kodeit.net>
---
 drivers/hwmon/applesmc.c | 91 +++++++++++++++++++++-------------------
 1 file changed, 49 insertions(+), 42 deletions(-)

diff --git a/drivers/hwmon/applesmc.c b/drivers/hwmon/applesmc.c
index 62211b590a61..39ed0bb21365 100644
--- a/drivers/hwmon/applesmc.c
+++ b/drivers/hwmon/applesmc.c
@@ -35,10 +35,11 @@
 #include <linux/err.h>
 #include <linux/bits.h>
 
+#define APPLESMC_PORT_BASE	0x300
 /* data port used by Apple SMC */
-#define APPLESMC_DATA_PORT	0x300
+#define APPLESMC_DATA_PORT	0
 /* command/status port used by Apple SMC */
-#define APPLESMC_CMD_PORT	0x304
+#define APPLESMC_CMD_PORT	4
 
 #define APPLESMC_NR_PORTS	32 /* 0x300-0x31f */
 
@@ -140,6 +141,8 @@ struct applesmc_device {
 	struct platform_device *dev;
 	struct applesmc_registers reg;
 
+	u16 port_base;
+
 	s16 rest_x;
 	s16 rest_y;
 
@@ -169,7 +172,7 @@ static const int debug;
  * run out past 500ms.
  */
 
-static int wait_status(u8 val, u8 mask)
+static int wait_status(struct applesmc_device *smc, u8 val, u8 mask)
 {
 	u8 status;
 	int us;
@@ -177,7 +180,7 @@ static int wait_status(u8 val, u8 mask)
 
 	us = APPLESMC_MIN_WAIT;
 	for (i = 0; i < 24 ; i++) {
-		status = inb(APPLESMC_CMD_PORT);
+		status = inb(smc->port_base + APPLESMC_CMD_PORT);
 		if ((status & mask) == val)
 			return 0;
 		usleep_range(us, us * 2);
@@ -189,11 +192,11 @@ static int wait_status(u8 val, u8 mask)
 
 /* send_byte - Write to SMC data port. Callers must hold applesmc_lock. */
 
-static int send_byte(u8 cmd, u16 port)
+static int send_byte(struct applesmc_device *smc, u8 cmd, u16 port)
 {
 	int status;
 
-	status = wait_status(0, SMC_STATUS_IB_CLOSED);
+	status = wait_status(smc, 0, SMC_STATUS_IB_CLOSED);
 	if (status)
 		return status;
 	/*
@@ -202,24 +205,24 @@ static int send_byte(u8 cmd, u16 port)
 	 * this extra read may not happen if status returns both
 	 * simultaneously and this would appear to be required.
 	 */
-	status = wait_status(SMC_STATUS_BUSY, SMC_STATUS_BUSY);
+	status = wait_status(smc, SMC_STATUS_BUSY, SMC_STATUS_BUSY);
 	if (status)
 		return status;
 
-	outb(cmd, port);
+	outb(cmd, smc->port_base + port);
 	return 0;
 }
 
 /* send_command - Write a command to the SMC. Callers must hold applesmc_lock. */
 
-static int send_command(u8 cmd)
+static int send_command(struct applesmc_device *smc, u8 cmd)
 {
 	int ret;
 
-	ret = wait_status(0, SMC_STATUS_IB_CLOSED);
+	ret = wait_status(smc, 0, SMC_STATUS_IB_CLOSED);
 	if (ret)
 		return ret;
-	outb(cmd, APPLESMC_CMD_PORT);
+	outb(cmd, smc->port_base + APPLESMC_CMD_PORT);
 	return 0;
 }
 
@@ -229,108 +232,112 @@ static int send_command(u8 cmd)
  * If busy is stuck high after the command then the SMC is jammed.
  */
 
-static int smc_sane(void)
+static int smc_sane(struct applesmc_device *smc)
 {
 	int ret;
 
-	ret = wait_status(0, SMC_STATUS_BUSY);
+	ret = wait_status(smc, 0, SMC_STATUS_BUSY);
 	if (!ret)
 		return ret;
-	ret = send_command(APPLESMC_READ_CMD);
+	ret = send_command(smc, APPLESMC_READ_CMD);
 	if (ret)
 		return ret;
-	return wait_status(0, SMC_STATUS_BUSY);
+	return wait_status(smc, 0, SMC_STATUS_BUSY);
 }
 
-static int send_argument(const char *key)
+static int send_argument(struct applesmc_device *smc, const char *key)
 {
 	int i;
 
 	for (i = 0; i < 4; i++)
-		if (send_byte(key[i], APPLESMC_DATA_PORT))
+		if (send_byte(smc, key[i], APPLESMC_DATA_PORT))
 			return -EIO;
 	return 0;
 }
 
-static int read_smc(u8 cmd, const char *key, u8 *buffer, u8 len)
+static int read_smc(struct applesmc_device *smc, u8 cmd, const char *key,
+	u8 *buffer, u8 len)
 {
 	u8 status, data = 0;
 	int i;
 	int ret;
 
-	ret = smc_sane();
+	ret = smc_sane(smc);
 	if (ret)
 		return ret;
 
-	if (send_command(cmd) || send_argument(key)) {
+	if (send_command(smc, cmd) || send_argument(smc, key)) {
 		pr_warn("%.4s: read arg fail\n", key);
 		return -EIO;
 	}
 
 	/* This has no effect on newer (2012) SMCs */
-	if (send_byte(len, APPLESMC_DATA_PORT)) {
+	if (send_byte(smc, len, APPLESMC_DATA_PORT)) {
 		pr_warn("%.4s: read len fail\n", key);
 		return -EIO;
 	}
 
 	for (i = 0; i < len; i++) {
-		if (wait_status(SMC_STATUS_AWAITING_DATA | SMC_STATUS_BUSY,
+		if (wait_status(smc,
+				SMC_STATUS_AWAITING_DATA | SMC_STATUS_BUSY,
 				SMC_STATUS_AWAITING_DATA | SMC_STATUS_BUSY)) {
 			pr_warn("%.4s: read data[%d] fail\n", key, i);
 			return -EIO;
 		}
-		buffer[i] = inb(APPLESMC_DATA_PORT);
+		buffer[i] = inb(smc->port_base + APPLESMC_DATA_PORT);
 	}
 
 	/* Read the data port until bit0 is cleared */
 	for (i = 0; i < 16; i++) {
 		udelay(APPLESMC_MIN_WAIT);
-		status = inb(APPLESMC_CMD_PORT);
+		status = inb(smc->port_base + APPLESMC_CMD_PORT);
 		if (!(status & SMC_STATUS_AWAITING_DATA))
 			break;
-		data = inb(APPLESMC_DATA_PORT);
+		data = inb(smc->port_base + APPLESMC_DATA_PORT);
 	}
 	if (i)
 		pr_warn("flushed %d bytes, last value is: %d\n", i, data);
 
-	return wait_status(0, SMC_STATUS_BUSY);
+	return wait_status(smc, 0, SMC_STATUS_BUSY);
 }
 
-static int write_smc(u8 cmd, const char *key, const u8 *buffer, u8 len)
+static int write_smc(struct applesmc_device *smc, u8 cmd, const char *key,
+	const u8 *buffer, u8 len)
 {
 	int i;
 	int ret;
 
-	ret = smc_sane();
+	ret = smc_sane(smc);
 	if (ret)
 		return ret;
 
-	if (send_command(cmd) || send_argument(key)) {
+	if (send_command(smc, cmd) || send_argument(smc, key)) {
 		pr_warn("%s: write arg fail\n", key);
 		return -EIO;
 	}
 
-	if (send_byte(len, APPLESMC_DATA_PORT)) {
+	if (send_byte(smc, len, APPLESMC_DATA_PORT)) {
 		pr_warn("%.4s: write len fail\n", key);
 		return -EIO;
 	}
 
 	for (i = 0; i < len; i++) {
-		if (send_byte(buffer[i], APPLESMC_DATA_PORT)) {
+		if (send_byte(smc, buffer[i], APPLESMC_DATA_PORT)) {
 			pr_warn("%s: write data fail\n", key);
 			return -EIO;
 		}
 	}
 
-	return wait_status(0, SMC_STATUS_BUSY);
+	return wait_status(smc, 0, SMC_STATUS_BUSY);
 }
 
-static int read_register_count(unsigned int *count)
+static int read_register_count(struct applesmc_device *smc,
+	unsigned int *count)
 {
 	__be32 be;
 	int ret;
 
-	ret = read_smc(APPLESMC_READ_CMD, KEY_COUNT_KEY, (u8 *)&be, 4);
+	ret = read_smc(smc, APPLESMC_READ_CMD, KEY_COUNT_KEY, (u8 *)&be, 4);
 	if (ret)
 		return ret;
 
@@ -353,7 +360,7 @@ static int applesmc_read_entry(struct applesmc_device *smc,
 	if (entry->len != len)
 		return -EINVAL;
 	mutex_lock(&smc->reg.mutex);
-	ret = read_smc(APPLESMC_READ_CMD, entry->key, buf, len);
+	ret = read_smc(smc, APPLESMC_READ_CMD, entry->key, buf, len);
 	mutex_unlock(&smc->reg.mutex);
 
 	return ret;
@@ -367,7 +374,7 @@ static int applesmc_write_entry(struct applesmc_device *smc,
 	if (entry->len != len)
 		return -EINVAL;
 	mutex_lock(&smc->reg.mutex);
-	ret = write_smc(APPLESMC_WRITE_CMD, entry->key, buf, len);
+	ret = write_smc(smc, APPLESMC_WRITE_CMD, entry->key, buf, len);
 	mutex_unlock(&smc->reg.mutex);
 	return ret;
 }
@@ -388,10 +395,10 @@ static const struct applesmc_entry *applesmc_get_entry_by_index(
 	if (cache->valid)
 		goto out;
 	be = cpu_to_be32(index);
-	ret = read_smc(APPLESMC_GET_KEY_BY_INDEX_CMD, (u8 *)&be, key, 4);
+	ret = read_smc(smc, APPLESMC_GET_KEY_BY_INDEX_CMD, (u8 *)&be, key, 4);
 	if (ret)
 		goto out;
-	ret = read_smc(APPLESMC_GET_KEY_TYPE_CMD, key, info, 6);
+	ret = read_smc(smc, APPLESMC_GET_KEY_TYPE_CMD, key, info, 6);
 	if (ret)
 		goto out;
 
@@ -589,7 +596,7 @@ static int applesmc_init_smcreg_try(struct applesmc_device *smc)
 	if (s->init_complete)
 		return 0;
 
-	ret = read_register_count(&count);
+	ret = read_register_count(smc, &count);
 	if (ret)
 		return ret;
 
@@ -1468,7 +1475,7 @@ static int __init applesmc_init(void)
 		goto out;
 	}
 
-	if (!request_region(APPLESMC_DATA_PORT, APPLESMC_NR_PORTS,
+	if (!request_region(APPLESMC_PORT_BASE, APPLESMC_NR_PORTS,
 								"applesmc")) {
 		ret = -ENXIO;
 		goto out;
@@ -1490,7 +1497,7 @@ static int __init applesmc_init(void)
 out_driver:
 	platform_driver_unregister(&applesmc_driver);
 out_region:
-	release_region(APPLESMC_DATA_PORT, APPLESMC_NR_PORTS);
+	release_region(APPLESMC_PORT_BASE, APPLESMC_NR_PORTS);
 out:
 	pr_warn("driver init failed (ret=%d)!\n", ret);
 	return ret;
@@ -1500,7 +1507,7 @@ static void __exit applesmc_exit(void)
 {
 	platform_device_unregister(pdev);
 	platform_driver_unregister(&applesmc_driver);
-	release_region(APPLESMC_DATA_PORT, APPLESMC_NR_PORTS);
+	release_region(APPLESMC_PORT_BASE, APPLESMC_NR_PORTS);
 }
 
 module_init(applesmc_init);
-- 
2.30.0