PCMCIA: soc_common: add GPIO support for card status signals

Add GPIO support for reading the card status (card detect, ready,
battery voltage detect) signals into soc_common code.  As we want
interrupts from these GPIOs, this takes over the old irq handling
infrastructure for card status signals, which will now be managed
entirely by the soc_common code.

Acked-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

2 files changed, 127 insertions, 3 deletions

diff --git a/drivers/pcmcia/soc_common.c b/drivers/pcmcia/soc_common.c
index 84d90d5220ce..09a9a52ad650 100644
--- a/drivers/pcmcia/soc_common.c
+++ b/drivers/pcmcia/soc_common.c
@@ -32,6 +32,7 @@
 
 
 #include <linux/cpufreq.h>
+#include <linux/gpio.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
@@ -49,6 +50,8 @@
 
 #include "soc_common.h"
 
+static irqreturn_t soc_common_pcmcia_interrupt(int irq, void *dev);
+
 #ifdef CONFIG_PCMCIA_DEBUG
 
 static int pc_debug;
@@ -104,6 +107,93 @@ void soc_common_pcmcia_get_timing(struct soc_pcmcia_socket *skt,
 }
 EXPORT_SYMBOL(soc_common_pcmcia_get_timing);
 
+static void __soc_pcmcia_hw_shutdown(struct soc_pcmcia_socket *skt,
+        unsigned int nr)
+{
+        unsigned int i;
+
+        for (i = 0; i < nr; i++) {
+                if (skt->stat[i].irq)
+                        free_irq(skt->stat[i].irq, skt);
+                if (gpio_is_valid(skt->stat[i].gpio))
+                        gpio_free(skt->stat[i].gpio);
+        }
+
+        if (skt->ops->hw_shutdown)
+                skt->ops->hw_shutdown(skt);
+}
+
+static void soc_pcmcia_hw_shutdown(struct soc_pcmcia_socket *skt)
+{
+        __soc_pcmcia_hw_shutdown(skt, ARRAY_SIZE(skt->stat));
+}
+
+static int soc_pcmcia_hw_init(struct soc_pcmcia_socket *skt)
+{
+        int ret = 0, i;
+
+        if (skt->ops->hw_init) {
+                ret = skt->ops->hw_init(skt);
+                if (ret)
+                        return ret;
+        }
+
+        for (i = 0; i < ARRAY_SIZE(skt->stat); i++) {
+                if (gpio_is_valid(skt->stat[i].gpio)) {
+                        int irq;
+
+                        ret = gpio_request_one(skt->stat[i].gpio, GPIOF_IN,
+                                               skt->stat[i].name);
+                        if (ret) {
+                                __soc_pcmcia_hw_shutdown(skt, i);
+                                return ret;
+                        }
+
+                        irq = gpio_to_irq(skt->stat[i].gpio);
+
+                        if (i == SOC_STAT_RDY)
+                                skt->socket.pci_irq = irq;
+                        else
+                                skt->stat[i].irq = irq;
+                }
+
+                if (skt->stat[i].irq) {
+                        ret = request_irq(skt->stat[i].irq,
+                                          soc_common_pcmcia_interrupt,
+                                          IRQF_TRIGGER_NONE,
+                                          skt->stat[i].name, skt);
+                        if (ret) {
+                                if (gpio_is_valid(skt->stat[i].gpio))
+                                        gpio_free(skt->stat[i].gpio);
+                                __soc_pcmcia_hw_shutdown(skt, i);
+                                return ret;
+                        }
+                }
+        }
+
+        return ret;
+}
+
+static void soc_pcmcia_hw_enable(struct soc_pcmcia_socket *skt)
+{
+        int i;
+
+        for (i = 0; i < ARRAY_SIZE(skt->stat); i++)
+                if (skt->stat[i].irq) {
+                        irq_set_irq_type(skt->stat[i].irq, IRQ_TYPE_EDGE_RISING);
+                        irq_set_irq_type(skt->stat[i].irq, IRQ_TYPE_EDGE_BOTH);
+                }
+}
+
+static void soc_pcmcia_hw_disable(struct soc_pcmcia_socket *skt)
+{
+        int i;
+
+        for (i = 0; i < ARRAY_SIZE(skt->stat); i++)
+                if (skt->stat[i].irq)
+                        irq_set_irq_type(skt->stat[i].irq, IRQ_TYPE_NONE);
+}
+
 static unsigned int soc_common_pcmcia_skt_state(struct soc_pcmcia_socket *skt)
 {
         struct pcmcia_state state;
@@ -111,6 +201,22 @@ static unsigned int soc_common_pcmcia_skt_state(struct soc_pcmcia_socket *skt)
 
         memset(&state, 0, sizeof(struct pcmcia_state));
 
+        /* Make battery voltage state report 'good' */
+        state.bvd1 = 1;
+        state.bvd2 = 1;
+
+        /* CD is active low by default */
+        if (gpio_is_valid(skt->stat[SOC_STAT_CD].gpio))
+                state.detect = !gpio_get_value(skt->stat[SOC_STAT_CD].gpio);
+
+        /* RDY and BVD are active high by default */
+        if (gpio_is_valid(skt->stat[SOC_STAT_RDY].gpio))
+                state.ready = !!gpio_get_value(skt->stat[SOC_STAT_RDY].gpio);
+        if (gpio_is_valid(skt->stat[SOC_STAT_BVD1].gpio))
+                state.bvd1 = !!gpio_get_value(skt->stat[SOC_STAT_BVD1].gpio);
+        if (gpio_is_valid(skt->stat[SOC_STAT_BVD2].gpio))
+                state.bvd2 = !!gpio_get_value(skt->stat[SOC_STAT_BVD2].gpio);
+
         skt->ops->socket_state(skt, &state);
 
         stat = state.detect  ? SS_DETECT : 0;
@@ -188,6 +294,7 @@ static int soc_common_pcmcia_sock_init(struct pcmcia_socket *sock)
         debug(skt, 2, "initializing socket\n");
         if (skt->ops->socket_init)
                 skt->ops->socket_init(skt);
+        soc_pcmcia_hw_enable(skt);
         return 0;
 }
 
@@ -207,6 +314,7 @@ static int soc_common_pcmcia_suspend(struct pcmcia_socket *sock)
 
         debug(skt, 2, "suspending socket\n");
 
+        soc_pcmcia_hw_disable(skt);
         if (skt->ops->socket_suspend)
                 skt->ops->socket_suspend(skt);
 
@@ -638,10 +746,15 @@ module_exit(soc_pcmcia_cpufreq_unregister);
 void soc_pcmcia_init_one(struct soc_pcmcia_socket *skt,
         struct pcmcia_low_level *ops, struct device *dev)
 {
+        int i;
+
         skt->ops = ops;
         skt->socket.owner = ops->owner;
         skt->socket.dev.parent = dev;
         skt->socket.pci_irq = NO_IRQ;
+
+        for (i = 0; i < ARRAY_SIZE(skt->stat); i++)
+                skt->stat[i].gpio = -EINVAL;
 }
 EXPORT_SYMBOL(soc_pcmcia_init_one);
 
@@ -652,8 +765,9 @@ void soc_pcmcia_remove_one(struct soc_pcmcia_socket *skt)
 
         pcmcia_unregister_socket(&skt->socket);
 
-        skt->ops->hw_shutdown(skt);
+        soc_pcmcia_hw_shutdown(skt);
 
+        /* should not be required; violates some lowlevel drivers */
         soc_common_pcmcia_config_skt(skt, &dead_socket);
 
         list_del(&skt->node);
@@ -710,7 +824,7 @@ int soc_pcmcia_add_one(struct soc_pcmcia_socket *skt)
          */
         skt->ops->set_timing(skt);
 
-        ret = skt->ops->hw_init(skt);
+        ret = soc_pcmcia_hw_init(skt);
         if (ret)
                 goto out_err_6;
 
@@ -743,7 +857,7 @@ int soc_pcmcia_add_one(struct soc_pcmcia_socket *skt)
         pcmcia_unregister_socket(&skt->socket);
 
  out_err_7:
-        skt->ops->hw_shutdown(skt);
+        soc_pcmcia_hw_shutdown(skt);
  out_err_6:
         list_del(&skt->node);
         mutex_unlock(&soc_pcmcia_sockets_lock);
diff --git a/drivers/pcmcia/soc_common.h b/drivers/pcmcia/soc_common.h
index 3ff7ead11b1d..ebdfa6c16308 100644
--- a/drivers/pcmcia/soc_common.h
+++ b/drivers/pcmcia/soc_common.h
@@ -50,6 +50,16 @@ struct soc_pcmcia_socket {
         struct resource         res_attr;
         void __iomem            *virt_io;
 
+        struct {
+                int             gpio;
+                unsigned int    irq;
+                const char      *name;
+        } stat[4];
+#define SOC_STAT_CD             0       /* Card detect */
+#define SOC_STAT_BVD1           1       /* BATDEAD / IOSTSCHG */
+#define SOC_STAT_BVD2           2       /* BATWARN / IOSPKR */
+#define SOC_STAT_RDY            3       /* Ready / Interrupt */
+
         unsigned int            irq_state;
 
         struct timer_list       poll_timer;