powerpc: Convert power off logic to pm_power_off

The generic Linux framework to power off the machine is a function pointer
called pm_power_off. The trick about this pointer is that device drivers can
potentially implement it rather than board files.

Today on powerpc we set pm_power_off to invoke our generic full machine power
off logic which then calls ppc_md.power_off to invoke machine specific power
off.

However, when we want to add a power off GPIO via the "gpio-poweroff" driver,
this card house falls apart. That driver only registers itself if pm_power_off
is NULL to ensure it doesn't override board specific logic. However, since we
always set pm_power_off to the generic power off logic (which will just not
power off the machine if no ppc_md.power_off call is implemented), we can't
implement power off via the generic GPIO power off driver.

To fix this up, let's get rid of the ppc_md.power_off logic and just always use
pm_power_off as was intended. Then individual drivers such as the GPIO power off
driver can implement power off logic via that function pointer.

With this patch set applied and a few patches on top of QEMU that implement a
power off GPIO on the virt e500 machine, I can successfully turn off my virtual
machine after halt.

Signed-off-by: Alexander Graf <agraf@suse.de>
[mpe: Squash into one patch and update changelog based on cover letter]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

21 files changed, 66 insertions, 58 deletions

diff --git a/arch/powerpc/include/asm/machdep.h b/arch/powerpc/include/asm/machdep.h
index 307347f8ddbd..f15f15c92544 100644
--- a/arch/powerpc/include/asm/machdep.h
+++ b/arch/powerpc/include/asm/machdep.h
@@ -142,7 +142,6 @@ struct machdep_calls {
 #endif
 
         void            (*restart)(char *cmd);
-        void            (*power_off)(void);
         void            (*halt)(void);
         void            (*panic)(char *str);
         void            (*cpu_die)(void);
diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c
index 1362cd62b3fa..44c8d03558ac 100644
--- a/arch/powerpc/kernel/setup-common.c
+++ b/arch/powerpc/kernel/setup-common.c
@@ -139,8 +139,8 @@ void machine_restart(char *cmd)
 void machine_power_off(void)
 {
         machine_shutdown();
-        if (ppc_md.power_off)
-                ppc_md.power_off();
+        if (pm_power_off)
+                pm_power_off();
 #ifdef CONFIG_SMP
         smp_send_stop();
 #endif
@@ -151,7 +151,7 @@ void machine_power_off(void)
 /* Used by the G5 thermal driver */
 EXPORT_SYMBOL_GPL(machine_power_off);
 
-void (*pm_power_off)(void) = machine_power_off;
+void (*pm_power_off)(void);
 EXPORT_SYMBOL_GPL(pm_power_off);
 
 void machine_halt(void)
diff --git a/arch/powerpc/platforms/44x/ppc476.c b/arch/powerpc/platforms/44x/ppc476.c
index 58db9d083969..c11ce6516c8f 100644
--- a/arch/powerpc/platforms/44x/ppc476.c
+++ b/arch/powerpc/platforms/44x/ppc476.c
@@ -94,7 +94,7 @@ static int avr_probe(struct i2c_client *client,
 {
         avr_i2c_client = client;
         ppc_md.restart = avr_reset_system;
-        ppc_md.power_off = avr_power_off_system;
+        pm_power_off = avr_power_off_system;
         return 0;
 }
 
diff --git a/arch/powerpc/platforms/52xx/efika.c b/arch/powerpc/platforms/52xx/efika.c
index 3feffde9128d..6af651e69129 100644
--- a/arch/powerpc/platforms/52xx/efika.c
+++ b/arch/powerpc/platforms/52xx/efika.c
@@ -212,6 +212,8 @@ static int __init efika_probe(void)
         DMA_MODE_READ = 0x44;
         DMA_MODE_WRITE = 0x48;
 
+        pm_power_off = rtas_power_off;
+
         return 1;
 }
 
@@ -225,7 +227,6 @@ define_machine(efika)
         .init_IRQ               = mpc52xx_init_irq,
         .get_irq                = mpc52xx_get_irq,
         .restart                = rtas_restart,
-        .power_off              = rtas_power_off,
         .halt                   = rtas_halt,
         .set_rtc_time           = rtas_set_rtc_time,
         .get_rtc_time           = rtas_get_rtc_time,
diff --git a/arch/powerpc/platforms/83xx/mcu_mpc8349emitx.c b/arch/powerpc/platforms/83xx/mcu_mpc8349emitx.c
index 463fa91ee5b6..15e8021ddef9 100644
--- a/arch/powerpc/platforms/83xx/mcu_mpc8349emitx.c
+++ b/arch/powerpc/platforms/83xx/mcu_mpc8349emitx.c
@@ -167,10 +167,10 @@ static int mcu_probe(struct i2c_client *client, const struct i2c_device_id *id)
         if (ret)
                 goto err;
 
-        /* XXX: this is potentially racy, but there is no lock for ppc_md */
-        if (!ppc_md.power_off) {
+        /* XXX: this is potentially racy, but there is no lock for pm_power_off */
+        if (!pm_power_off) {
                 glob_mcu = mcu;
-                ppc_md.power_off = mcu_power_off;
+                pm_power_off = mcu_power_off;
                 dev_info(&client->dev, "will provide power-off service\n");
         }
 
@@ -197,7 +197,7 @@ static int mcu_remove(struct i2c_client *client)
         device_remove_file(&client->dev, &dev_attr_status);
 
         if (glob_mcu == mcu) {
-                ppc_md.power_off = NULL;
+                pm_power_off = NULL;
                 glob_mcu = NULL;
         }
 
diff --git a/arch/powerpc/platforms/85xx/corenet_generic.c b/arch/powerpc/platforms/85xx/corenet_generic.c
index e56b89a792ed..1f309ccb096e 100644
--- a/arch/powerpc/platforms/85xx/corenet_generic.c
+++ b/arch/powerpc/platforms/85xx/corenet_generic.c
@@ -170,7 +170,7 @@ static int __init corenet_generic_probe(void)
 
                         ppc_md.get_irq = ehv_pic_get_irq;
                         ppc_md.restart = fsl_hv_restart;
-                        ppc_md.power_off = fsl_hv_halt;
+                        pm_power_off = fsl_hv_halt;
                         ppc_md.halt = fsl_hv_halt;
 #ifdef CONFIG_SMP
                         /*
diff --git a/arch/powerpc/platforms/85xx/sgy_cts1000.c b/arch/powerpc/platforms/85xx/sgy_cts1000.c
index 8162b0412117..e149c9ec26ae 100644
--- a/arch/powerpc/platforms/85xx/sgy_cts1000.c
+++ b/arch/powerpc/platforms/85xx/sgy_cts1000.c
@@ -120,7 +120,7 @@ static int gpio_halt_probe(struct platform_device *pdev)
 
         /* Register our halt function */
         ppc_md.halt = gpio_halt_cb;
-        ppc_md.power_off = gpio_halt_cb;
+        pm_power_off = gpio_halt_cb;
 
         printk(KERN_INFO "gpio-halt: registered GPIO %d (%d trigger, %d"
                " irq).\n", gpio, trigger, irq);
@@ -137,7 +137,7 @@ static int gpio_halt_remove(struct platform_device *pdev)
                 free_irq(irq, halt_node);
 
                 ppc_md.halt = NULL;
-                ppc_md.power_off = NULL;
+                pm_power_off = NULL;
 
                 gpio_free(gpio);
 
diff --git a/arch/powerpc/platforms/cell/celleb_setup.c b/arch/powerpc/platforms/cell/celleb_setup.c
index 34e8ce2976aa..90be8ec51686 100644
--- a/arch/powerpc/platforms/cell/celleb_setup.c
+++ b/arch/powerpc/platforms/cell/celleb_setup.c
@@ -142,6 +142,7 @@ static int __init celleb_probe_beat(void)
         powerpc_firmware_features |= FW_FEATURE_CELLEB_ALWAYS
                 | FW_FEATURE_BEAT | FW_FEATURE_LPAR;
         hpte_init_beat_v3();
+        pm_power_off = beat_power_off;
 
         return 1;
 }
@@ -190,6 +191,7 @@ static int __init celleb_probe_native(void)
 
         powerpc_firmware_features |= FW_FEATURE_CELLEB_ALWAYS;
         hpte_init_native();
+        pm_power_off = rtas_power_off;
 
         return 1;
 }
@@ -204,7 +206,6 @@ define_machine(celleb_beat) {
         .setup_arch             = celleb_setup_arch_beat,
         .show_cpuinfo           = celleb_show_cpuinfo,
         .restart                = beat_restart,
-        .power_off              = beat_power_off,
         .halt                   = beat_halt,
         .get_rtc_time           = beat_get_rtc_time,
         .set_rtc_time           = beat_set_rtc_time,
@@ -230,7 +231,6 @@ define_machine(celleb_native) {
         .setup_arch             = celleb_setup_arch_native,
         .show_cpuinfo           = celleb_show_cpuinfo,
         .restart                = rtas_restart,
-        .power_off              = rtas_power_off,
         .halt                   = rtas_halt,
         .get_boot_time          = rtas_get_boot_time,
         .get_rtc_time           = rtas_get_rtc_time,
diff --git a/arch/powerpc/platforms/cell/qpace_setup.c b/arch/powerpc/platforms/cell/qpace_setup.c
index 6e3409d590ac..d328140dc6f5 100644
--- a/arch/powerpc/platforms/cell/qpace_setup.c
+++ b/arch/powerpc/platforms/cell/qpace_setup.c
@@ -127,6 +127,7 @@ static int __init qpace_probe(void)
                 return 0;
 
         hpte_init_native();
+        pm_power_off = rtas_power_off;
 
         return 1;
 }
@@ -137,7 +138,6 @@ define_machine(qpace) {
         .setup_arch             = qpace_setup_arch,
         .show_cpuinfo           = qpace_show_cpuinfo,
         .restart                = rtas_restart,
-        .power_off              = rtas_power_off,
         .halt                   = rtas_halt,
         .get_boot_time          = rtas_get_boot_time,
         .get_rtc_time           = rtas_get_rtc_time,
diff --git a/arch/powerpc/platforms/cell/setup.c b/arch/powerpc/platforms/cell/setup.c
index 6ae25fb62015..d62aa982d530 100644
--- a/arch/powerpc/platforms/cell/setup.c
+++ b/arch/powerpc/platforms/cell/setup.c
@@ -259,6 +259,7 @@ static int __init cell_probe(void)
                 return 0;
 
         hpte_init_native();
+        pm_power_off = rtas_power_off;
 
         return 1;
 }
@@ -269,7 +270,6 @@ define_machine(cell) {
         .setup_arch             = cell_setup_arch,
         .show_cpuinfo           = cell_show_cpuinfo,
         .restart                = rtas_restart,
-        .power_off              = rtas_power_off,
         .halt                   = rtas_halt,
         .get_boot_time          = rtas_get_boot_time,
         .get_rtc_time           = rtas_get_rtc_time,
diff --git a/arch/powerpc/platforms/chrp/setup.c b/arch/powerpc/platforms/chrp/setup.c
index 5b77b1919fd2..860a59eb8ea2 100644
--- a/arch/powerpc/platforms/chrp/setup.c
+++ b/arch/powerpc/platforms/chrp/setup.c
@@ -585,6 +585,8 @@ static int __init chrp_probe(void)
         DMA_MODE_READ = 0x44;
         DMA_MODE_WRITE = 0x48;
 
+        pm_power_off = rtas_power_off;
+
         return 1;
 }
 
@@ -597,7 +599,6 @@ define_machine(chrp) {
         .show_cpuinfo           = chrp_show_cpuinfo,
         .init_IRQ               = chrp_init_IRQ,
         .restart                = rtas_restart,
-        .power_off              = rtas_power_off,
         .halt                   = rtas_halt,
         .time_init              = chrp_time_init,
         .set_rtc_time           = chrp_set_rtc_time,
diff --git a/arch/powerpc/platforms/embedded6xx/gamecube.c b/arch/powerpc/platforms/embedded6xx/gamecube.c
index bd4ba5d7d568..fe0ed6ee285e 100644
--- a/arch/powerpc/platforms/embedded6xx/gamecube.c
+++ b/arch/powerpc/platforms/embedded6xx/gamecube.c
@@ -67,6 +67,8 @@ static int __init gamecube_probe(void)
         if (!of_flat_dt_is_compatible(dt_root, "nintendo,gamecube"))
                 return 0;
 
+        pm_power_off = gamecube_power_off;
+
         return 1;
 }
 
@@ -80,7 +82,6 @@ define_machine(gamecube) {
         .probe                  = gamecube_probe,
         .init_early             = gamecube_init_early,
         .restart                = gamecube_restart,
-        .power_off              = gamecube_power_off,
         .halt                   = gamecube_halt,
         .init_IRQ               = flipper_pic_probe,
         .get_irq                = flipper_pic_get_irq,
diff --git a/arch/powerpc/platforms/embedded6xx/linkstation.c b/arch/powerpc/platforms/embedded6xx/linkstation.c
index 168e1d80b2e5..540eeb58d3f0 100644
--- a/arch/powerpc/platforms/embedded6xx/linkstation.c
+++ b/arch/powerpc/platforms/embedded6xx/linkstation.c
@@ -147,6 +147,9 @@ static int __init linkstation_probe(void)
 
         if (!of_flat_dt_is_compatible(root, "linkstation"))
                 return 0;
+
+        pm_power_off = linkstation_power_off;
+
         return 1;
 }
 
@@ -158,7 +161,6 @@ define_machine(linkstation){
         .show_cpuinfo           = linkstation_show_cpuinfo,
         .get_irq                = mpic_get_irq,
         .restart                = linkstation_restart,
-        .power_off              = linkstation_power_off,
         .halt                   = linkstation_halt,
         .calibrate_decr         = generic_calibrate_decr,
 };
diff --git a/arch/powerpc/platforms/embedded6xx/wii.c b/arch/powerpc/platforms/embedded6xx/wii.c
index 388e29bab8f6..352592d3e44e 100644
--- a/arch/powerpc/platforms/embedded6xx/wii.c
+++ b/arch/powerpc/platforms/embedded6xx/wii.c
@@ -211,6 +211,8 @@ static int __init wii_probe(void)
         if (!of_flat_dt_is_compatible(dt_root, "nintendo,wii"))
                 return 0;
 
+        pm_power_off = wii_power_off;
+
         return 1;
 }
 
@@ -226,7 +228,6 @@ define_machine(wii) {
         .init_early             = wii_init_early,
         .setup_arch             = wii_setup_arch,
         .restart                = wii_restart,
-        .power_off              = wii_power_off,
         .halt                   = wii_halt,
         .init_IRQ               = wii_pic_probe,
         .get_irq                = flipper_pic_get_irq,
diff --git a/arch/powerpc/platforms/maple/setup.c b/arch/powerpc/platforms/maple/setup.c
index cb1b0b35a0c6..56b85cd61aaf 100644
--- a/arch/powerpc/platforms/maple/setup.c
+++ b/arch/powerpc/platforms/maple/setup.c
@@ -169,7 +169,7 @@ static void __init maple_use_rtas_reboot_and_halt_if_present(void)
         if (rtas_service_present("system-reboot") &&
             rtas_service_present("power-off")) {
                 ppc_md.restart = rtas_restart;
-                ppc_md.power_off = rtas_power_off;
+                pm_power_off = rtas_power_off;
                 ppc_md.halt = rtas_halt;
         }
 }
@@ -312,6 +312,7 @@ static int __init maple_probe(void)
         alloc_dart_table();
 
         hpte_init_native();
+        pm_power_off = maple_power_off;
 
         return 1;
 }
@@ -325,7 +326,6 @@ define_machine(maple) {
         .pci_irq_fixup          = maple_pci_irq_fixup,
         .pci_get_legacy_ide_irq = maple_pci_get_legacy_ide_irq,
         .restart                = maple_restart,
-        .power_off              = maple_power_off,
         .halt                   = maple_halt,
         .get_boot_time          = maple_get_boot_time,
         .set_rtc_time           = maple_set_rtc_time,
diff --git a/arch/powerpc/platforms/powermac/setup.c b/arch/powerpc/platforms/powermac/setup.c
index b127a29ac526..713d36d45d1d 100644
--- a/arch/powerpc/platforms/powermac/setup.c
+++ b/arch/powerpc/platforms/powermac/setup.c
@@ -632,6 +632,8 @@ static int __init pmac_probe(void)
         smu_cmdbuf_abs = memblock_alloc_base(4096, 4096, 0x80000000UL);
 #endif /* CONFIG_PMAC_SMU */
 
+        pm_power_off = pmac_power_off;
+
         return 1;
 }
 
@@ -663,7 +665,6 @@ define_machine(powermac) {
         .get_irq                = NULL, /* changed later */
         .pci_irq_fixup          = pmac_pci_irq_fixup,
         .restart                = pmac_restart,
-        .power_off              = pmac_power_off,
         .halt                   = pmac_halt,
         .time_init              = pmac_time_init,
         .get_boot_time          = pmac_get_boot_time,
diff --git a/arch/powerpc/platforms/powernv/setup.c b/arch/powerpc/platforms/powernv/setup.c
index 3f9546d8a51f..941831d67cb2 100644
--- a/arch/powerpc/platforms/powernv/setup.c
+++ b/arch/powerpc/platforms/powernv/setup.c
@@ -268,7 +268,7 @@ static void __init pnv_setup_machdep_opal(void)
         ppc_md.get_rtc_time = opal_get_rtc_time;
         ppc_md.set_rtc_time = opal_set_rtc_time;
         ppc_md.restart = pnv_restart;
-        ppc_md.power_off = pnv_power_off;
+        pm_power_off = pnv_power_off;
         ppc_md.halt = pnv_halt;
         ppc_md.machine_check_exception = opal_machine_check;
         ppc_md.mce_check_early_recovery = opal_mce_check_early_recovery;
@@ -285,7 +285,7 @@ static void __init pnv_setup_machdep_rtas(void)
                 ppc_md.set_rtc_time = rtas_set_rtc_time;
         }
         ppc_md.restart = rtas_restart;
-        ppc_md.power_off = rtas_power_off;
+        pm_power_off = rtas_power_off;
         ppc_md.halt = rtas_halt;
 }
 #endif /* CONFIG_PPC_POWERNV_RTAS */
diff --git a/arch/powerpc/platforms/ps3/setup.c b/arch/powerpc/platforms/ps3/setup.c
index 3f509f86432c..009a2004b876 100644
--- a/arch/powerpc/platforms/ps3/setup.c
+++ b/arch/powerpc/platforms/ps3/setup.c
@@ -248,6 +248,7 @@ static int __init ps3_probe(void)
         ps3_mm_init();
         ps3_mm_vas_create(&htab_size);
         ps3_hpte_init(htab_size);
+        pm_power_off = ps3_power_off;
 
         DBG(" <- %s:%d\n", __func__, __LINE__);
         return 1;
@@ -278,7 +279,6 @@ define_machine(ps3) {
         .calibrate_decr                 = ps3_calibrate_decr,
         .progress                       = ps3_progress,
         .restart                        = ps3_restart,
-        .power_off                      = ps3_power_off,
         .halt                           = ps3_halt,
 #if defined(CONFIG_KEXEC)
         .kexec_cpu_down                 = ps3_kexec_cpu_down,
diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 125c589eeef5..db0fc0c07568 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -659,6 +659,34 @@ static void __init pSeries_init_early(void)
         pr_debug(" <- pSeries_init_early()\n");
 }
 
+/**
+ * pseries_power_off - tell firmware about how to power off the system.
+ *
+ * This function calls either the power-off rtas token in normal cases
+ * or the ibm,power-off-ups token (if present & requested) in case of
+ * a power failure. If power-off token is used, power on will only be
+ * possible with power button press. If ibm,power-off-ups token is used
+ * it will allow auto poweron after power is restored.
+ */
+static void pseries_power_off(void)
+{
+        int rc;
+        int rtas_poweroff_ups_token = rtas_token("ibm,power-off-ups");
+
+        if (rtas_flash_term_hook)
+                rtas_flash_term_hook(SYS_POWER_OFF);
+
+        if (rtas_poweron_auto == 0 ||
+                rtas_poweroff_ups_token == RTAS_UNKNOWN_SERVICE) {
+                rc = rtas_call(rtas_token("power-off"), 2, 1, NULL, -1, -1);
+                printk(KERN_INFO "RTAS power-off returned %d\n", rc);
+        } else {
+                rc = rtas_call(rtas_poweroff_ups_token, 0, 1, NULL);
+                printk(KERN_INFO "RTAS ibm,power-off-ups returned %d\n", rc);
+        }
+        for (;;);
+}
+
 /*
  * Called very early, MMU is off, device-tree isn't unflattened
  */
@@ -741,6 +769,8 @@ static int __init pSeries_probe(void)
         else
                 hpte_init_native();
 
+        pm_power_off = pseries_power_off;
+
         pr_debug("Machine is%s LPAR !\n",
                  (powerpc_firmware_features & FW_FEATURE_LPAR) ? "" : " not");
 
@@ -754,34 +784,6 @@ static int pSeries_pci_probe_mode(struct pci_bus *bus)
         return PCI_PROBE_NORMAL;
 }
 
-/**
- * pSeries_power_off - tell firmware about how to power off the system.
- *
- * This function calls either the power-off rtas token in normal cases
- * or the ibm,power-off-ups token (if present & requested) in case of
- * a power failure. If power-off token is used, power on will only be
- * possible with power button press. If ibm,power-off-ups token is used
- * it will allow auto poweron after power is restored.
- */
-static void pSeries_power_off(void)
-{
-        int rc;
-        int rtas_poweroff_ups_token = rtas_token("ibm,power-off-ups");
-
-        if (rtas_flash_term_hook)
-                rtas_flash_term_hook(SYS_POWER_OFF);
-
-        if (rtas_poweron_auto == 0 ||
-                rtas_poweroff_ups_token == RTAS_UNKNOWN_SERVICE) {
-                rc = rtas_call(rtas_token("power-off"), 2, 1, NULL, -1, -1);
-                printk(KERN_INFO "RTAS power-off returned %d\n", rc);
-        } else {
-                rc = rtas_call(rtas_poweroff_ups_token, 0, 1, NULL);
-                printk(KERN_INFO "RTAS ibm,power-off-ups returned %d\n", rc);
-        }
-        for (;;);
-}
-
 #ifndef CONFIG_PCI
 void pSeries_final_fixup(void) { }
 #endif
@@ -796,7 +798,6 @@ define_machine(pseries) {
         .pcibios_fixup          = pSeries_final_fixup,
         .pci_probe_mode         = pSeries_pci_probe_mode,
         .restart                = rtas_restart,
-        .power_off              = pSeries_power_off,
         .halt                   = rtas_halt,
         .panic                  = rtas_os_term,
         .get_boot_time          = rtas_get_boot_time,
diff --git a/arch/powerpc/sysdev/fsl_soc.c b/arch/powerpc/sysdev/fsl_soc.c
index ffd1169ebaab..1e04568da3b9 100644
--- a/arch/powerpc/sysdev/fsl_soc.c
+++ b/arch/powerpc/sysdev/fsl_soc.c
@@ -238,7 +238,7 @@ void fsl_hv_restart(char *cmd)
 /*
  * Halt the current partition
  *
- * This function should be assigned to the ppc_md.power_off and ppc_md.halt
+ * This function should be assigned to the pm_power_off and ppc_md.halt
  * function pointers, to shut down the partition when we're running under
  * the Freescale hypervisor.
  */
diff --git a/arch/powerpc/xmon/xmon.c b/arch/powerpc/xmon/xmon.c
index b988b5addf86..506d25681fe3 100644
--- a/arch/powerpc/xmon/xmon.c
+++ b/arch/powerpc/xmon/xmon.c
@@ -981,7 +981,8 @@ static void bootcmds(void)
         else if (cmd == 'h')
                 ppc_md.halt();
         else if (cmd == 'p')
-                ppc_md.power_off();
+                if (pm_power_off)
+                        pm_power_off();
 }
 
 static int cpu_cmd(void)