Commit eb994594 authored by Andrew Jeffery's avatar Andrew Jeffery Committed by Corey Minyard
Browse files

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: default avatarAndrew Jeffery <andrew@aj.id.au>
Reviewed-by: default avatarCédric Le Goater <clg@kaod.org>
Signed-off-by: default avatarCorey Minyard <cminyard@mvista.com>
parent db3b7e13

drivers/char/ipmi/Kconfig

+2 −1
Original line number Diff line number Diff line
@@ -78,7 +78,8 @@ config IPMI_POWEROFF 
endif # IPMI_HANDLER



config ASPEED_BT_IPMI_BMC

	depends on ARCH_ASPEED

	depends on ARCH_ASPEED || COMPILE_TEST

       depends on REGMAP && REGMAP_MMIO && MFD_SYSCON

	tristate "BT IPMI bmc driver"

	help

	  Provides a driver for the BT (Block Transfer) IPMI interface

drivers/char/ipmi/bt-bmc.c

+59 −21
Original line number Diff line number Diff line
@@ -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);



	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);

	bt_bmc->base = devm_ioremap_resource(&pdev->dev, res);

	if (IS_ERR(bt_bmc->base))

		return PTR_ERR(bt_bmc->base);

		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) |

	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,

		  bt_bmc->base + BT_CR0);

		     BT_CR0_ENABLE_IBT);



	clr_b_busy(bt_bmc);

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