diff options
author | Andrew Jeffery <andrew@aj.id.au> | 2017-02-21 01:53:00 +1030 |
---|---|---|
committer | Corey Minyard <cminyard@mvista.com> | 2017-02-20 11:00:48 -0600 |
commit | eb994594bc22220976f367c03ffa141580aa45e4 (patch) | |
tree | 293b499831e468cf9d4a0f25fd7aca540fbe91f8 /drivers/char/ipmi/bt-bmc.c | |
parent | db3b7e134185b27e6073618c1ad7eca1e4473eb4 (diff) | |
download | linux-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.c | 80 |
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, ®); + 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); |