1 files changed, 281 insertions, 0 deletions

diff --git a/drivers/modem/m6718_spi/util.c b/drivers/modem/m6718_spi/util.c
new file mode 100644
index 00000000000..9026f4427dd
--- /dev/null
+++ b/drivers/modem/m6718_spi/util.c
@@ -0,0 +1,281 @@
+/*
+ * Copyright (C) ST-Ericsson SA 2010,2011
+ *
+ * Author: Chris Blair <chris.blair@stericsson.com> for ST-Ericsson
+ *
+ * License terms: GNU General Public License (GPL) version 2
+ *
+ * U9500 <-> M6718 IPC protocol implementation using SPI:
+ *   utility functions.
+ */
+#include <linux/gpio.h>
+#include <linux/modem/m6718_spi/modem_driver.h>
+#include "modem_util.h"
+
+#define MODEM_COMMS_TMO_MS  (5000) /* 0 == no timeout */
+#define SLAVE_STABLE_TMO_MS (1000)
+
+#define DRIVER_NAME "ipcspi" /* name used when reserving gpio pins */
+
+
+bool ipc_util_channel_is_loopback(u8 channel)
+{
+	return channel == MODEM_M6718_SPI_CHN_MASTER_LOOPBACK0 ||
+		channel == MODEM_M6718_SPI_CHN_MASTER_LOOPBACK1;
+}
+
+u32 ipc_util_make_l2_header(u8 channel, u32 len)
+{
+	return ((channel & 0xf) << 28) | (len & 0x000fffff);
+}
+
+u8 ipc_util_get_l2_channel(u32 hdr)
+{
+	return hdr >> 28;
+}
+
+u32 ipc_util_get_l2_length(u32 hdr)
+{
+	return hdr & 0x000fffff;
+}
+
+u32 ipc_util_make_l1_header(u8 cmd, u8 counter, u32 len)
+{
+	return (cmd << 28) |
+		((counter & 0x000000ff) << 20) |
+		(len & 0x000fffff);
+}
+
+u8 ipc_util_get_l1_cmd(u32 hdr)
+{
+	return hdr >> 28;
+}
+
+u8 ipc_util_get_l1_counter(u32 hdr)
+{
+	return (hdr >> 20) & 0x000000ff;
+}
+
+u32 ipc_util_get_l1_length(u32 hdr)
+{
+	return hdr & 0x000fffff;
+}
+
+u8 ipc_util_get_l1_bootresp_ver(u32 bootresp)
+{
+	return bootresp & 0x000000ff;
+}
+
+int ipc_util_ss_level_active(struct ipc_link_context *context)
+{
+	return context->link->gpio.ss_active == 0 ? 0 : 1;
+}
+
+int ipc_util_ss_level_inactive(struct ipc_link_context *context)
+{
+	return !ipc_util_ss_level_active(context);
+}
+
+int ipc_util_int_level_active(struct ipc_link_context *context)
+{
+	return context->link->gpio.int_active == 0 ? 0 : 1;
+}
+
+int ipc_util_int_level_inactive(struct ipc_link_context *context)
+{
+	return !ipc_util_int_level_active(context);
+}
+
+void ipc_util_deactivate_ss(struct ipc_link_context *context)
+{
+	gpio_set_value(context->link->gpio.ss_pin,
+		ipc_util_ss_level_inactive(context));
+
+	dev_dbg(&context->sdev->dev,
+		"link %d: deactivated SS\n", context->link->id);
+}
+
+void ipc_util_activate_ss(struct ipc_link_context *context)
+{
+	gpio_set_value(context->link->gpio.ss_pin,
+		ipc_util_ss_level_active(context));
+
+	dev_dbg(&context->sdev->dev,
+		"link %d: activated SS\n", context->link->id);
+}
+
+void ipc_util_activate_ss_with_tmo(struct ipc_link_context *context)
+{
+	gpio_set_value(context->link->gpio.ss_pin,
+		ipc_util_ss_level_active(context));
+
+#if MODEM_COMMS_TMO_MS == 0
+	dev_dbg(&context->sdev->dev,
+		 "link %d: activated SS (timeout is disabled)\n",
+		 context->link->id);
+#else
+	context->comms_timer.expires = jiffies +
+		((MODEM_COMMS_TMO_MS * HZ) / 1000);
+	add_timer(&context->comms_timer);
+
+	dev_dbg(&context->sdev->dev,
+		"link %d: activated SS with timeout\n", context->link->id);
+#endif
+}
+
+bool ipc_util_int_is_active(struct ipc_link_context *context)
+{
+	return gpio_get_value(context->link->gpio.int_pin) ==
+		ipc_util_int_level_active(context);
+}
+
+bool ipc_util_link_is_idle(struct ipc_link_context *context)
+{
+	if (context->state == NULL)
+		return false;
+
+	switch (context->state->id) {
+	case IPC_SM_IDL:
+		return true;
+	default:
+		return false;
+	}
+}
+
+void ipc_util_start_slave_stable_timer(struct ipc_link_context *context)
+{
+	context->slave_stable_timer.expires =
+		jiffies + ((SLAVE_STABLE_TMO_MS * HZ) / 1000);
+	add_timer(&context->slave_stable_timer);
+}
+
+void ipc_util_spi_message_prepare(struct ipc_link_context *link_context,
+	void *tx_buf, void *rx_buf, int len)
+{
+	struct spi_transfer *tfr = &link_context->spi_transfer;
+	struct spi_message *msg = &link_context->spi_message;
+
+	tfr->tx_buf = tx_buf;
+	tfr->rx_buf = rx_buf;
+	tfr->len    = len;
+	msg->context = link_context;
+}
+
+void ipc_util_spi_message_init(struct ipc_link_context *link_context,
+	void (*complete)(void *))
+{
+	struct spi_message *msg = &link_context->spi_message;
+	struct spi_transfer *tfr = &link_context->spi_transfer;
+
+	tfr->bits_per_word = 16;
+
+	/* common init of transfer - use default from board device */
+	tfr->cs_change = 0;
+	tfr->speed_hz = 0;
+	tfr->delay_usecs = 0;
+
+	/* common init of message */
+	spi_message_init(msg);
+	msg->spi = link_context->sdev;
+	msg->complete = complete;
+	spi_message_add_tail(tfr, msg);
+}
+
+bool ipc_util_link_gpio_request(struct ipc_link_context *context,
+	irqreturn_t (*irqhnd)(int, void*))
+{
+	struct spi_device *sdev = context->sdev;
+	struct modem_m6718_spi_link_platform_data *link = context->link;
+	unsigned long irqflags;
+
+	if (gpio_request(link->gpio.ss_pin, DRIVER_NAME) < 0) {
+		dev_err(&sdev->dev,
+			"link %d error: failed to get gpio %d for SS pin\n",
+			link->id,
+			link->gpio.ss_pin);
+		return false;
+	}
+	if (gpio_request(link->gpio.int_pin, DRIVER_NAME) < 0) {
+		dev_err(&sdev->dev,
+			"link %d error: failed to get gpio %d for INT pin\n",
+			link->id,
+			link->gpio.int_pin);
+		return false;
+	}
+
+	if (ipc_util_int_level_active(context) == 1)
+		irqflags = IRQF_TRIGGER_RISING;
+	else
+		irqflags = IRQF_TRIGGER_FALLING;
+
+	if (request_irq(GPIO_TO_IRQ(link->gpio.int_pin),
+			irqhnd,
+			irqflags,
+			DRIVER_NAME,
+			context) < 0) {
+		dev_err(&sdev->dev,
+			"link %d error: could not get irq %d\n",
+			link->id, GPIO_TO_IRQ(link->gpio.int_pin));
+		return false;
+	}
+	return true;
+}
+
+bool ipc_util_link_gpio_config(struct ipc_link_context *context)
+{
+	struct spi_device *sdev = context->sdev;
+	struct modem_m6718_spi_link_platform_data *link = context->link;
+
+	if (atomic_read(&context->gpio_configured) == 1)
+		return true;
+
+	dev_dbg(&sdev->dev, "link %d: configuring GPIO\n", link->id);
+
+	ipc_util_deactivate_ss(context);
+	gpio_direction_input(link->gpio.int_pin);
+	if (enable_irq_wake(GPIO_TO_IRQ(link->gpio.int_pin)) < 0) {
+		dev_err(&sdev->dev,
+			"link %d error: failed to enable wake on INT\n",
+			link->id);
+		return false;
+	}
+
+	atomic_set(&context->state_int, gpio_get_value(link->gpio.int_pin));
+	atomic_set(&context->gpio_configured, 1);
+	return true;
+}
+
+bool ipc_util_link_gpio_unconfig(struct ipc_link_context *context)
+{
+	struct spi_device *sdev = context->sdev;
+	struct modem_m6718_spi_link_platform_data *link = context->link;
+
+	if (atomic_read(&context->gpio_configured) == 0)
+		return true;
+
+	dev_dbg(&sdev->dev, "link %d: un-configuring GPIO\n", link->id);
+
+	/* SS: output anyway, just make sure it is low */
+	gpio_set_value(link->gpio.ss_pin, 0);
+
+	/* INT: disable system-wake, reconfigure as output-low */
+	disable_irq_wake(GPIO_TO_IRQ(link->gpio.int_pin));
+	gpio_direction_output(link->gpio.int_pin, 0);
+	atomic_set(&context->gpio_configured, 0);
+	return true;
+}
+
+bool ipc_util_link_is_suspended(struct ipc_link_context *context)
+{
+	return atomic_read(&context->suspended) == 1;
+}
+
+void ipc_util_suspend_link(struct ipc_link_context *context)
+{
+	atomic_set(&context->suspended, 1);
+}
+
+void ipc_util_resume_link(struct ipc_link_context *context)
+{
+	atomic_set(&context->suspended, 0);
+}