[PATCH 2/2] sata highbank: add bit-banged SGPIO driver support
Mark Langsdorf
mark.langsdorf at calxeda.com
Fri May 31 06:17:31 EST 2013
Highbank supports SGPIO by bit-banging out the SGPIO signals over
three GPIO pins defined in the DTB. Add support for this SGPIO
functionality.
Signed-off-by: Mark Langsdorf <mark.langsdorf at calxeda.com>
---
.../devicetree/bindings/ata/ahci-platform.txt | 9 ++
arch/arm/boot/dts/ecx-common.dtsi | 1 +
drivers/ata/sata_highbank.c | 128 ++++++++++++++++++++-
3 files changed, 133 insertions(+), 5 deletions(-)
diff --git a/Documentation/devicetree/bindings/ata/ahci-platform.txt b/Documentation/devicetree/bindings/ata/ahci-platform.txt
index b519f9b..123b7ae 100644
--- a/Documentation/devicetree/bindings/ata/ahci-platform.txt
+++ b/Documentation/devicetree/bindings/ata/ahci-platform.txt
@@ -12,6 +12,15 @@ Optional properties:
- calxeda,port-phys: phandle-combophy and lane assignment, which maps each
SATA port to a combophy and a lane within that
combophy
+- calxeda,sgpio-gpio: phandle-gpio bank, bit offset, and default on or off,
+ which indicates that the driver supports SGPIO
+ indicator lights using the indicated GPIOs
+- calxeda,led-order : a u32 array that map port numbers to offsets within the
+ SGPIO bitstream. By default, port 0 has offset 4
+ and the other ports are offset by their port number
+ less 1. if calxeda,sgpio-gpio is used and that port
+ to led mapping is incorrect, this array should have
+ each port's offset within the bitstream.
- dma-coherent : Present if dma operations are coherent
Example:
diff --git a/arch/arm/boot/dts/ecx-common.dtsi b/arch/arm/boot/dts/ecx-common.dtsi
index d61b535..8c1d643 100644
--- a/arch/arm/boot/dts/ecx-common.dtsi
+++ b/arch/arm/boot/dts/ecx-common.dtsi
@@ -33,6 +33,7 @@
calxeda,port-phys = <&combophy5 0 &combophy0 0
&combophy0 1 &combophy0 2
&combophy0 3>;
+ calxeda,sgpio-gpio =<&gpioh 5 1 &gpioh 6 1 &gpioh 7 1>;
};
sdhci at ffe0e000 {
diff --git a/drivers/ata/sata_highbank.c b/drivers/ata/sata_highbank.c
index b20aa96..d48f708 100644
--- a/drivers/ata/sata_highbank.c
+++ b/drivers/ata/sata_highbank.c
@@ -33,6 +33,9 @@
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/export.h>
+#include <linux/gpio.h>
+#include <linux/of_gpio.h>
+
#include "ahci.h"
#define CPHY_MAP(dev, addr) ((((dev) & 0x1f) << 7) | (((addr) >> 9) & 0x7f))
@@ -66,6 +69,124 @@ struct phy_lane_info {
};
static struct phy_lane_info port_data[CPHY_PORT_COUNT];
+static DEFINE_SPINLOCK(sgpio_lock);
+#define SCLOCK 0
+#define SLOAD 1
+#define SDATA 2
+static unsigned ecx_sgpio[3];
+static unsigned long ecx_sgpio_pattern;
+static int port_to_sgpio[] = { 4, 0, 1, 2, 3};
+static int n_ports;
+
+#define ACTIVITY_BITS 0x300000 // 0x7
+#define ACTIVITY_SHIFT 2
+#define LOCATE_BITS 0x80000 // 0x38
+#define LOCATE_SHIFT 1
+#define FAULT_BITS 0x400000 // 0x1c0
+#define FAULT_SHIFT 1
+#define SGPIO_BIT(port, shift) 1 << (3 * port_to_sgpio[(port)] + \
+ (shift))
+static void ecx_parse_sgpio(u32 port, u32 state)
+{
+ if (state == 0) {
+ ecx_sgpio_pattern &= ~(SGPIO_BIT(port, ACTIVITY_SHIFT) |
+ SGPIO_BIT(port, LOCATE_SHIFT) |
+ SGPIO_BIT(port, FAULT_SHIFT));
+ return;
+ }
+ if (state & ACTIVITY_BITS)
+ ecx_sgpio_pattern |= SGPIO_BIT(port, ACTIVITY_SHIFT);
+ if (state & LOCATE_BITS)
+ ecx_sgpio_pattern |= SGPIO_BIT(port, LOCATE_SHIFT);
+ if (state & FAULT_BITS)
+ ecx_sgpio_pattern |= SGPIO_BIT(port, FAULT_SHIFT);
+}
+
+/*
+ * Tell the LED controller that the signal has changed by raising the clock
+ * line for 50 uS and then lowering it for 50 uS.
+ */
+static void ecx_led_cycle_clock(void)
+{
+ gpio_set_value(ecx_sgpio[SCLOCK], 1);
+ udelay(50);
+ gpio_set_value(ecx_sgpio[SCLOCK], 0);
+ udelay(50);
+}
+
+static ssize_t ecx_transmit_led_message(struct ata_port *ap, u32 state,
+ ssize_t size)
+{
+ struct ahci_host_priv *hpriv = ap->host->private_data;
+ struct ahci_port_priv *pp = ap->private_data;
+ unsigned long flags;
+ int pmp, i;
+ struct ahci_em_priv *emp;
+ u32 sgpio_out;
+
+ /* get the slot number from the message */
+ pmp = (state & EM_MSG_LED_PMP_SLOT) >> 8;
+ if (pmp < EM_MAX_SLOTS)
+ emp = &pp->em_priv[pmp];
+ else
+ return -EINVAL;
+
+ if (!hpriv->em_msg_type & EM_MSG_TYPE_LED)
+ return size;
+
+ spin_lock_irqsave(&sgpio_lock, flags);
+ ecx_parse_sgpio(ap->port_no, state);
+ sgpio_out = ecx_sgpio_pattern;
+ gpio_set_value(ecx_sgpio[SLOAD], 1);
+ ecx_led_cycle_clock();
+ gpio_set_value(ecx_sgpio[SLOAD], 0);
+ for (i = 0; i < (3 * n_ports); i++) {
+ gpio_set_value(ecx_sgpio[SDATA], sgpio_out & 1);
+ sgpio_out >>= 1;
+ ecx_led_cycle_clock();
+ }
+
+ /* save off new led state for port/slot */
+ emp->led_state = state;
+
+ spin_unlock_irqrestore(&sgpio_lock, flags);
+ return size;
+}
+
+void highbank_set_em_messages(struct device *dev, struct ahci_host_priv *hpriv,
+ struct ata_port_info *pi)
+{
+ struct device_node *np = dev->of_node;
+ int i;
+ int err;
+
+ for (i = 0;i < 3; i++) {
+ ecx_sgpio[i] = of_get_named_gpio(np, "calxeda,sgpio-gpio", i);
+ if (IS_ERR_VALUE(ecx_sgpio[i]))
+ return;
+
+ err = gpio_request(ecx_sgpio[i], "CX SGPIO");
+ if (err) {
+ printk(KERN_ERR
+ "sata_highbank gpio_request %d failed: %d\n",
+ i, err);
+ return;
+ }
+ gpio_direction_output(ecx_sgpio[i], 1);
+ }
+ /* there's a default ordering, but give it an optional override */
+ for (i = 0; i < n_ports; i++) {
+ of_property_read_u32_array(np, "calxeda,led-order",
+ port_to_sgpio, i);
+ }
+
+ /* store em_loc */
+ hpriv->em_loc = 0;
+ hpriv->em_buf_sz = 4;
+ hpriv->em_msg_type = EM_MSG_TYPE_LED;
+ pi->flags |= ATA_FLAG_EM | ATA_FLAG_SW_ACTIVITY;
+}
+
static u32 __combo_phy_reg_read(u8 sata_port, u32 addr)
{
u32 data;
@@ -241,6 +362,7 @@ static int ahci_highbank_hardreset(struct ata_link *link, unsigned int *class,
static struct ata_port_operations ahci_highbank_ops = {
.inherits = &ahci_ops,
.hardreset = ahci_highbank_hardreset,
+ .transmit_led_message = ecx_transmit_led_message,
};
static const struct ata_port_info ahci_highbank_port_info = {
@@ -267,7 +389,6 @@ static int ahci_highbank_probe(struct platform_device *pdev)
struct ata_host *host;
struct resource *mem;
int irq;
- int n_ports;
int i;
int rc;
struct ata_port_info pi = ahci_highbank_port_info;
@@ -313,7 +434,7 @@ static int ahci_highbank_probe(struct platform_device *pdev)
if (hpriv->cap & HOST_CAP_PMP)
pi.flags |= ATA_FLAG_PMP;
- ahci_set_em_messages(hpriv, &pi);
+ highbank_set_em_messages(dev, hpriv, &pi);
/* CAP.NP sometimes indicate the index of the last enabled
* port, at other times, that of the last possible port, so
@@ -333,9 +454,6 @@ static int ahci_highbank_probe(struct platform_device *pdev)
if (!(hpriv->cap & HOST_CAP_SSS) || ahci_ignore_sss)
host->flags |= ATA_HOST_PARALLEL_SCAN;
- if (pi.flags & ATA_FLAG_EM)
- ahci_reset_em(host);
-
for (i = 0; i < host->n_ports; i++) {
struct ata_port *ap = host->ports[i];
--
1.8.1.4
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