[PATCH 1/2] simatic-ipc: convert to use common P2SB accessor

From: Henning Schild
Date: Tue Mar 08 2022 - 14:35:53 EST


Since we have a common P2SB accessor in tree we may use it instead of
open coded variants.

Replace custom code by p2sb_bar() call.

Signed-off-by: Henning Schild <henning.schild@xxxxxxxxxxx>
---
drivers/leds/simple/Kconfig | 1 +
drivers/leds/simple/simatic-ipc-leds.c | 14 +++----
drivers/platform/x86/simatic-ipc.c | 38 -------------------
drivers/watchdog/Kconfig | 1 +
drivers/watchdog/simatic-ipc-wdt.c | 15 ++++----
.../platform_data/x86/simatic-ipc-base.h | 2 -
6 files changed, 17 insertions(+), 54 deletions(-)

diff --git a/drivers/leds/simple/Kconfig b/drivers/leds/simple/Kconfig
index 9f6a68336659..9293e6b36c75 100644
--- a/drivers/leds/simple/Kconfig
+++ b/drivers/leds/simple/Kconfig
@@ -3,6 +3,7 @@ config LEDS_SIEMENS_SIMATIC_IPC
tristate "LED driver for Siemens Simatic IPCs"
depends on LEDS_CLASS
depends on SIEMENS_SIMATIC_IPC
+ select P2SB if X86
help
This option enables support for the LEDs of several Industrial PCs
from Siemens.
diff --git a/drivers/leds/simple/simatic-ipc-leds.c b/drivers/leds/simple/simatic-ipc-leds.c
index ff2c96e73241..215ef5b74236 100644
--- a/drivers/leds/simple/simatic-ipc-leds.c
+++ b/drivers/leds/simple/simatic-ipc-leds.c
@@ -15,6 +15,7 @@
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/pci.h>
+#include <linux/platform_data/x86/p2sb.h>
#include <linux/platform_data/x86/simatic-ipc-base.h>
#include <linux/platform_device.h>
#include <linux/sizes.h>
@@ -38,8 +39,8 @@ static struct simatic_ipc_led simatic_ipc_leds_io[] = {
{ }
};

-/* the actual start will be discovered with PCI, 0 is a placeholder */
-struct resource simatic_ipc_led_mem_res = DEFINE_RES_MEM_NAMED(0, SZ_4K, KBUILD_MODNAME);
+/* the actual start will be discovered with p2sb, 0 is a placeholder */
+struct resource simatic_ipc_led_mem_res = DEFINE_RES_MEM_NAMED(0, 0, KBUILD_MODNAME);

static void *simatic_ipc_led_memory;

@@ -143,14 +144,13 @@ static int simatic_ipc_leds_probe(struct platform_device *pdev)
ipcled = simatic_ipc_leds_mem;
type = IORESOURCE_MEM;

- /* get GPIO base from PCI */
- res->start = simatic_ipc_get_membase0(PCI_DEVFN(13, 0));
- if (res->start == 0)
- return -ENODEV;
+ err = p2sb_bar(NULL, 0, res);
+ if (err)
+ return err;

/* do the final address calculation */
res->start = res->start + (0xC5 << 16);
- res->end += res->start;
+ res->end = res->start + SZ_4K - 1;

simatic_ipc_led_memory = devm_ioremap_resource(dev, res);
if (IS_ERR(simatic_ipc_led_memory))
diff --git a/drivers/platform/x86/simatic-ipc.c b/drivers/platform/x86/simatic-ipc.c
index b599cda5ba3c..26c35e1660cb 100644
--- a/drivers/platform/x86/simatic-ipc.c
+++ b/drivers/platform/x86/simatic-ipc.c
@@ -101,44 +101,6 @@ static int register_platform_devices(u32 station_id)
return 0;
}

-/* FIXME: this should eventually be done with generic P2SB discovery code
- * the individual drivers for watchdogs and LEDs access memory that implements
- * GPIO, but pinctrl will not come up because of missing ACPI entries
- *
- * While there is no conflict a cleaner solution would be to somehow bring up
- * pinctrl even with these ACPI entries missing, and base the drivers on pinctrl.
- * After which the following function could be dropped, together with the code
- * poking the memory.
- */
-/*
- * Get membase address from PCI, used in leds and wdt module. Here we read
- * the bar0. The final address calculation is done in the appropriate modules
- */
-u32 simatic_ipc_get_membase0(unsigned int p2sb)
-{
- struct pci_bus *bus;
- u32 bar0 = 0;
- /*
- * The GPIO memory is in bar0 of the hidden P2SB device.
- * Unhide the device to have a quick look at it, before we hide it
- * again.
- * Also grab the pci rescan lock so that device does not get discovered
- * and remapped while it is visible.
- * This code is inspired by drivers/mfd/lpc_ich.c
- */
- bus = pci_find_bus(0, 0);
- pci_lock_rescan_remove();
- pci_bus_write_config_byte(bus, p2sb, 0xE1, 0x0);
- pci_bus_read_config_dword(bus, p2sb, PCI_BASE_ADDRESS_0, &bar0);
-
- bar0 &= ~0xf;
- pci_bus_write_config_byte(bus, p2sb, 0xE1, 0x1);
- pci_unlock_rescan_remove();
-
- return bar0;
-}
-EXPORT_SYMBOL(simatic_ipc_get_membase0);
-
static int __init simatic_ipc_init_module(void)
{
const struct dmi_system_id *match;
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index c8fa79da23b3..ce44a942fc68 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -1628,6 +1628,7 @@ config SIEMENS_SIMATIC_IPC_WDT
tristate "Siemens Simatic IPC Watchdog"
depends on SIEMENS_SIMATIC_IPC
select WATCHDOG_CORE
+ select P2SB if X86
help
This driver adds support for several watchdogs found in Industrial
PCs from Siemens.
diff --git a/drivers/watchdog/simatic-ipc-wdt.c b/drivers/watchdog/simatic-ipc-wdt.c
index 8bac793c63fb..6599695dc672 100644
--- a/drivers/watchdog/simatic-ipc-wdt.c
+++ b/drivers/watchdog/simatic-ipc-wdt.c
@@ -16,6 +16,7 @@
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
+#include <linux/platform_data/x86/p2sb.h>
#include <linux/platform_data/x86/simatic-ipc-base.h>
#include <linux/platform_device.h>
#include <linux/sizes.h>
@@ -54,9 +55,9 @@ static struct resource io_resource_trigger =
DEFINE_RES_IO_NAMED(WD_TRIGGER_IOADR, SZ_1,
KBUILD_MODNAME " WD_TRIGGER_IOADR");

-/* the actual start will be discovered with pci, 0 is a placeholder */
+/* the actual start will be discovered with p2sb, 0 is a placeholder */
static struct resource mem_resource =
- DEFINE_RES_MEM_NAMED(0, SZ_4, "WD_RESET_BASE_ADR");
+ DEFINE_RES_MEM_NAMED(0, 0, "WD_RESET_BASE_ADR");

static u32 wd_timeout_table[] = {2, 4, 6, 8, 16, 32, 48, 64 };
static void __iomem *wd_reset_base_addr;
@@ -150,6 +151,7 @@ static int simatic_ipc_wdt_probe(struct platform_device *pdev)
struct simatic_ipc_platform *plat = pdev->dev.platform_data;
struct device *dev = &pdev->dev;
struct resource *res;
+ int ret;

switch (plat->devmode) {
case SIMATIC_IPC_DEVICE_227E:
@@ -190,15 +192,14 @@ static int simatic_ipc_wdt_probe(struct platform_device *pdev)
if (plat->devmode == SIMATIC_IPC_DEVICE_427E) {
res = &mem_resource;

- /* get GPIO base from PCI */
- res->start = simatic_ipc_get_membase0(PCI_DEVFN(0x1f, 1));
- if (res->start == 0)
- return -ENODEV;
+ ret = p2sb_bar(NULL, 0, res);
+ if (ret)
+ return ret;

/* do the final address calculation */
res->start = res->start + (GPIO_COMMUNITY0_PORT_ID << 16) +
PAD_CFG_DW0_GPP_A_23;
- res->end += res->start;
+ res->end = res->start + SZ_4 - 1;

wd_reset_base_addr = devm_ioremap_resource(dev, res);
if (IS_ERR(wd_reset_base_addr))
diff --git a/include/linux/platform_data/x86/simatic-ipc-base.h b/include/linux/platform_data/x86/simatic-ipc-base.h
index 62d2bc774067..39fefd48cf4d 100644
--- a/include/linux/platform_data/x86/simatic-ipc-base.h
+++ b/include/linux/platform_data/x86/simatic-ipc-base.h
@@ -24,6 +24,4 @@ struct simatic_ipc_platform {
u8 devmode;
};

-u32 simatic_ipc_get_membase0(unsigned int p2sb);
-
#endif /* __PLATFORM_DATA_X86_SIMATIC_IPC_BASE_H */
--
2.34.1