mfd: watchdog: iTCO_wdt: Expose watchdog properties using platform data

Intel Sunrisepoint (Skylake PCH) has the iTCO watchdog accessible across
the SMBus, unlike previous generations of PCH/ICH where it was on the
LPC bus. Because it's on the SMBus, it doesn't make sense to pass around
a 'struct lpc_ich_info', and leaking the type of bus into the iTCO
watchdog driver is kind of backwards anyway.

This change introduces a new 'struct itco_wdt_platform_data' for use
inside the iTCO watchdog driver and by the upcoming Intel Sunrisepoint
code, which neatly avoids having to include lpc_ich headers in the i801
i2c driver.

This change is overdue because lpc_ich_info has already found its way
into other TCO watchdog users, notably the intel_pmc_ipc driver where
the watchdog actually isn't on the LPC bus as far as I can see.

A simple translation layer is provided for converting from the existing
'struct lpc_ich_info' inside the lpc_ich mfd driver.

Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Acked-by: Darren Hart <dvhart@linux.intel.com> [drivers/x86 refactoring]
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

drivers/platform/x86/intel_pmc_ipc.c

@@ -33,7 +33,7 @@
 #include <linux/suspend.h>
 #include <linux/acpi.h>
 #include <asm/intel_pmc_ipc.h>
-#include <linux/mfd/lpc_ich.h>
+#include <linux/platform_data/itco_wdt.h>
 
 /*
  * IPC registers
@@ -460,9 +460,9 @@ static struct resource tco_res[] = {
 	},
 };
 
-static struct lpc_ich_info tco_info = {
+static struct itco_wdt_platform_data tco_info = {
 	.name = "Apollo Lake SoC",
-	.iTCO_version = 3,
+	.version = 3,
 };
 
 static int ipc_create_punit_device(void)
@@ -539,8 +539,7 @@ static int ipc_create_tco_device(void)
 		goto err;
 	}
 
-	ret = platform_device_add_data(pdev, &tco_info,
-				       sizeof(struct lpc_ich_info));
+	ret = platform_device_add_data(pdev, &tco_info, sizeof(tco_info));
 	if (ret) {
 		dev_err(ipcdev.dev, "Failed to add tco platform data\n");
 		goto err;