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authorAndrew Jeffery <andrew@aj.id.au>2017-02-21 01:53:00 +1030
committerCorey Minyard <cminyard@mvista.com>2017-02-20 11:00:48 -0600
commiteb994594bc22220976f367c03ffa141580aa45e4 (patch)
tree293b499831e468cf9d4a0f25fd7aca540fbe91f8 /drivers/char/ipmi/bt-bmc.c
parentdb3b7e134185b27e6073618c1ad7eca1e4473eb4 (diff)
downloadlinux-eb994594bc22220976f367c03ffa141580aa45e4.tar.bz2
ipmi: bt-bmc: Use a regmap for register access
The registers for the bt-bmc device live under the Aspeed LPC controller. Devicetree bindings have recently been introduced for the LPC controller where the "host" portion of the LPC register space is described as a syscon device. Future devicetrees describing the bt-bmc device should nest its node under the appropriate "simple-mfd", "syscon" compatible node. This change allows the bt-bmc driver to function with both syscon and non-syscon- based devicetree descriptions by always using a regmap for register access, either retrieved from the parent syscon device or instantiated if none exists. Signed-off-by: Andrew Jeffery <andrew@aj.id.au> Reviewed-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Corey Minyard <cminyard@mvista.com>
Diffstat (limited to 'drivers/char/ipmi/bt-bmc.c')
-rw-r--r--drivers/char/ipmi/bt-bmc.c80
1 files changed, 59 insertions, 21 deletions
diff --git a/drivers/char/ipmi/bt-bmc.c b/drivers/char/ipmi/bt-bmc.c
index fc9e8891eae3..d6f5d9eb102d 100644
--- a/drivers/char/ipmi/bt-bmc.c
+++ b/drivers/char/ipmi/bt-bmc.c
@@ -12,10 +12,13 @@
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/io.h>
+#include <linux/mfd/syscon.h>
#include <linux/miscdevice.h>
#include <linux/module.h>
+#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/poll.h>
+#include <linux/regmap.h>
#include <linux/sched.h>
#include <linux/timer.h>
@@ -60,7 +63,8 @@
struct bt_bmc {
struct device dev;
struct miscdevice miscdev;
- void __iomem *base;
+ struct regmap *map;
+ int offset;
int irq;
wait_queue_head_t queue;
struct timer_list poll_timer;
@@ -69,14 +73,29 @@ struct bt_bmc {
static atomic_t open_count = ATOMIC_INIT(0);
+static const struct regmap_config bt_regmap_cfg = {
+ .reg_bits = 32,
+ .val_bits = 32,
+ .reg_stride = 4,
+};
+
static u8 bt_inb(struct bt_bmc *bt_bmc, int reg)
{
- return ioread8(bt_bmc->base + reg);
+ uint32_t val = 0;
+ int rc;
+
+ rc = regmap_read(bt_bmc->map, bt_bmc->offset + reg, &val);
+ WARN(rc != 0, "regmap_read() failed: %d\n", rc);
+
+ return rc == 0 ? (u8) val : 0;
}
static void bt_outb(struct bt_bmc *bt_bmc, u8 data, int reg)
{
- iowrite8(data, bt_bmc->base + reg);
+ int rc;
+
+ rc = regmap_write(bt_bmc->map, bt_bmc->offset + reg, data);
+ WARN(rc != 0, "regmap_write() failed: %d\n", rc);
}
static void clr_rd_ptr(struct bt_bmc *bt_bmc)
@@ -367,14 +386,18 @@ static irqreturn_t bt_bmc_irq(int irq, void *arg)
{
struct bt_bmc *bt_bmc = arg;
u32 reg;
+ int rc;
+
+ rc = regmap_read(bt_bmc->map, bt_bmc->offset + BT_CR2, &reg);
+ if (rc)
+ return IRQ_NONE;
- reg = ioread32(bt_bmc->base + BT_CR2);
reg &= BT_CR2_IRQ_H2B | BT_CR2_IRQ_HBUSY;
if (!reg)
return IRQ_NONE;
/* ack pending IRQs */
- iowrite32(reg, bt_bmc->base + BT_CR2);
+ regmap_write(bt_bmc->map, bt_bmc->offset + BT_CR2, reg);
wake_up(&bt_bmc->queue);
return IRQ_HANDLED;
@@ -384,7 +407,6 @@ static int bt_bmc_config_irq(struct bt_bmc *bt_bmc,
struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
- u32 reg;
int rc;
bt_bmc->irq = platform_get_irq(pdev, 0);
@@ -405,18 +427,17 @@ static int bt_bmc_config_irq(struct bt_bmc *bt_bmc,
* will be cleared (along with B2H) when we can write the next
* message to the BT buffer
*/
- reg = ioread32(bt_bmc->base + BT_CR1);
- reg |= BT_CR1_IRQ_H2B | BT_CR1_IRQ_HBUSY;
- iowrite32(reg, bt_bmc->base + BT_CR1);
+ rc = regmap_update_bits(bt_bmc->map, bt_bmc->offset + BT_CR1,
+ (BT_CR1_IRQ_H2B | BT_CR1_IRQ_HBUSY),
+ (BT_CR1_IRQ_H2B | BT_CR1_IRQ_HBUSY));
- return 0;
+ return rc;
}
static int bt_bmc_probe(struct platform_device *pdev)
{
struct bt_bmc *bt_bmc;
struct device *dev;
- struct resource *res;
int rc;
if (!pdev || !pdev->dev.of_node)
@@ -431,10 +452,27 @@ static int bt_bmc_probe(struct platform_device *pdev)
dev_set_drvdata(&pdev->dev, bt_bmc);
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- bt_bmc->base = devm_ioremap_resource(&pdev->dev, res);
- if (IS_ERR(bt_bmc->base))
- return PTR_ERR(bt_bmc->base);
+ bt_bmc->map = syscon_node_to_regmap(pdev->dev.parent->of_node);
+ if (IS_ERR(bt_bmc->map)) {
+ struct resource *res;
+ void __iomem *base;
+
+ /*
+ * Assume it's not the MFD-based devicetree description, in
+ * which case generate a regmap ourselves
+ */
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(base))
+ return PTR_ERR(base);
+
+ bt_bmc->map = devm_regmap_init_mmio(dev, base, &bt_regmap_cfg);
+ bt_bmc->offset = 0;
+ } else {
+ rc = of_property_read_u32(dev->of_node, "reg", &bt_bmc->offset);
+ if (rc)
+ return rc;
+ }
mutex_init(&bt_bmc->mutex);
init_waitqueue_head(&bt_bmc->queue);
@@ -461,12 +499,12 @@ static int bt_bmc_probe(struct platform_device *pdev)
add_timer(&bt_bmc->poll_timer);
}
- iowrite32((BT_IO_BASE << BT_CR0_IO_BASE) |
- (BT_IRQ << BT_CR0_IRQ) |
- BT_CR0_EN_CLR_SLV_RDP |
- BT_CR0_EN_CLR_SLV_WRP |
- BT_CR0_ENABLE_IBT,
- bt_bmc->base + BT_CR0);
+ regmap_write(bt_bmc->map, bt_bmc->offset + BT_CR0,
+ (BT_IO_BASE << BT_CR0_IO_BASE) |
+ (BT_IRQ << BT_CR0_IRQ) |
+ BT_CR0_EN_CLR_SLV_RDP |
+ BT_CR0_EN_CLR_SLV_WRP |
+ BT_CR0_ENABLE_IBT);
clr_b_busy(bt_bmc);