Revision - b4cd08a - i2c: rcar: disable runtime PM correctly in slave mode

Revision b4cd08aa1f53c831e67dc5c6bc9f9acff27abcba authored by Wolfram Sang on 16 December 2015, 19:05:18 UTC, committed by Wolfram Sang on 19 December 2015, 11:00:37 UTC

i2c: rcar: disable runtime PM correctly in slave mode

When we also are I2C slave, we need to disable runtime PM because the
address detection mechanism needs to be active all the time. However, we
can reenable runtime PM once the slave instance was unregistered. So,
use pm_runtime_get_sync/put to achieve this, since it has proper
refcounting. pm_runtime_allow/forbid is like a global knob controllable
from userspace which is unsuitable here.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org

1 parent e79e72c

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parport_sunbpp.c

/* parport_sunbpp.c: Parallel-port routines for SBUS
 * 
 * Author: Derrick J. Brashear <shadow@dementia.org>
 *
 * based on work by:
 *          Phil Blundell <philb@gnu.org>
 *          Tim Waugh <tim@cyberelk.demon.co.uk>
 *	    Jose Renau <renau@acm.org>
 *          David Campbell <campbell@tirian.che.curtin.edu.au>
 *          Grant Guenther <grant@torque.net>
 *          Eddie C. Dost <ecd@skynet.be>
 *          Stephen Williams (steve@icarus.com)
 *          Gus Baldauf (gbaldauf@ix.netcom.com)
 *          Peter Zaitcev
 *          Tom Dyas
 *
 * Updated to new SBUS device framework: David S. Miller <davem@davemloft.net>
 * 
 */

#include <linux/string.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/ioport.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/of.h>
#include <linux/of_device.h>

#include <linux/parport.h>

#include <asm/ptrace.h>
#include <linux/interrupt.h>

#include <asm/io.h>
#include <asm/oplib.h>           /* OpenProm Library */
#include <asm/dma.h>             /* BPP uses LSI 64854 for DMA */
#include <asm/irq.h>
#include <asm/sunbpp.h>

#undef __SUNBPP_DEBUG
#ifdef __SUNBPP_DEBUG
#define dprintk(x) printk x
#else
#define dprintk(x)
#endif

static void parport_sunbpp_disable_irq(struct parport *p)
{
	struct bpp_regs __iomem *regs = (struct bpp_regs __iomem *)p->base;
	u32 tmp;

	tmp = sbus_readl(&regs->p_csr);
	tmp &= ~DMA_INT_ENAB;
	sbus_writel(tmp, &regs->p_csr);
}

static void parport_sunbpp_enable_irq(struct parport *p)
{
	struct bpp_regs __iomem *regs = (struct bpp_regs __iomem *)p->base;
	u32 tmp;

	tmp = sbus_readl(&regs->p_csr);
	tmp |= DMA_INT_ENAB;
	sbus_writel(tmp, &regs->p_csr);
}

static void parport_sunbpp_write_data(struct parport *p, unsigned char d)
{
	struct bpp_regs __iomem *regs = (struct bpp_regs __iomem *)p->base;

	sbus_writeb(d, &regs->p_dr);
	dprintk((KERN_DEBUG "wrote 0x%x\n", d));
}

static unsigned char parport_sunbpp_read_data(struct parport *p)
{
	struct bpp_regs __iomem *regs = (struct bpp_regs __iomem *)p->base;

	return sbus_readb(&regs->p_dr);
}

static unsigned char status_sunbpp_to_pc(struct parport *p)
{
	struct bpp_regs __iomem *regs = (struct bpp_regs __iomem *)p->base;
	unsigned char bits = 0;
	unsigned char value_tcr = sbus_readb(&regs->p_tcr);
	unsigned char value_ir = sbus_readb(&regs->p_ir);

	if (!(value_ir & P_IR_ERR))
		bits |= PARPORT_STATUS_ERROR;
	if (!(value_ir & P_IR_SLCT))
		bits |= PARPORT_STATUS_SELECT;
	if (!(value_ir & P_IR_PE))
		bits |= PARPORT_STATUS_PAPEROUT;
	if (value_tcr & P_TCR_ACK)
		bits |= PARPORT_STATUS_ACK;
	if (!(value_tcr & P_TCR_BUSY))
		bits |= PARPORT_STATUS_BUSY;

	dprintk((KERN_DEBUG "tcr 0x%x ir 0x%x\n", value_tcr, value_ir));
	dprintk((KERN_DEBUG "read status 0x%x\n", bits));
	return bits;
}

static unsigned char control_sunbpp_to_pc(struct parport *p)
{
	struct bpp_regs __iomem *regs = (struct bpp_regs __iomem *)p->base;
	unsigned char bits = 0;
	unsigned char value_tcr = sbus_readb(&regs->p_tcr);
	unsigned char value_or = sbus_readb(&regs->p_or);

	if (!(value_tcr & P_TCR_DS))
		bits |= PARPORT_CONTROL_STROBE;
	if (!(value_or & P_OR_AFXN))
		bits |= PARPORT_CONTROL_AUTOFD;
	if (!(value_or & P_OR_INIT))
		bits |= PARPORT_CONTROL_INIT;
	if (value_or & P_OR_SLCT_IN)
		bits |= PARPORT_CONTROL_SELECT;

	dprintk((KERN_DEBUG "tcr 0x%x or 0x%x\n", value_tcr, value_or));
	dprintk((KERN_DEBUG "read control 0x%x\n", bits));
	return bits;
}

static unsigned char parport_sunbpp_read_control(struct parport *p)
{
	return control_sunbpp_to_pc(p);
}

static unsigned char parport_sunbpp_frob_control(struct parport *p,
						 unsigned char mask,
						 unsigned char val)
{
	struct bpp_regs __iomem *regs = (struct bpp_regs __iomem *)p->base;
	unsigned char value_tcr = sbus_readb(&regs->p_tcr);
	unsigned char value_or = sbus_readb(&regs->p_or);

	dprintk((KERN_DEBUG "frob1: tcr 0x%x or 0x%x\n",
		 value_tcr, value_or));
	if (mask & PARPORT_CONTROL_STROBE) {
		if (val & PARPORT_CONTROL_STROBE) {
			value_tcr &= ~P_TCR_DS;
		} else {
			value_tcr |= P_TCR_DS;
		}
	}
	if (mask & PARPORT_CONTROL_AUTOFD) {
		if (val & PARPORT_CONTROL_AUTOFD) {
			value_or &= ~P_OR_AFXN;
		} else {
			value_or |= P_OR_AFXN;
		}
	}
	if (mask & PARPORT_CONTROL_INIT) {
		if (val & PARPORT_CONTROL_INIT) {
			value_or &= ~P_OR_INIT;
		} else {
			value_or |= P_OR_INIT;
		}
	}
	if (mask & PARPORT_CONTROL_SELECT) {
		if (val & PARPORT_CONTROL_SELECT) {
			value_or |= P_OR_SLCT_IN;
		} else {
			value_or &= ~P_OR_SLCT_IN;
		}
	}

	sbus_writeb(value_or, &regs->p_or);
	sbus_writeb(value_tcr, &regs->p_tcr);
	dprintk((KERN_DEBUG "frob2: tcr 0x%x or 0x%x\n",
		 value_tcr, value_or));
	return parport_sunbpp_read_control(p);
}

static void parport_sunbpp_write_control(struct parport *p, unsigned char d)
{
	const unsigned char wm = (PARPORT_CONTROL_STROBE |
				  PARPORT_CONTROL_AUTOFD |
				  PARPORT_CONTROL_INIT |
				  PARPORT_CONTROL_SELECT);

	parport_sunbpp_frob_control (p, wm, d & wm);
}

static unsigned char parport_sunbpp_read_status(struct parport *p)
{
	return status_sunbpp_to_pc(p);
}

static void parport_sunbpp_data_forward (struct parport *p)
{
	struct bpp_regs __iomem *regs = (struct bpp_regs __iomem *)p->base;
	unsigned char value_tcr = sbus_readb(&regs->p_tcr);

	dprintk((KERN_DEBUG "forward\n"));
	value_tcr &= ~P_TCR_DIR;
	sbus_writeb(value_tcr, &regs->p_tcr);
}

static void parport_sunbpp_data_reverse (struct parport *p)
{
	struct bpp_regs __iomem *regs = (struct bpp_regs __iomem *)p->base;
	u8 val = sbus_readb(&regs->p_tcr);

	dprintk((KERN_DEBUG "reverse\n"));
	val |= P_TCR_DIR;
	sbus_writeb(val, &regs->p_tcr);
}

static void parport_sunbpp_init_state(struct pardevice *dev, struct parport_state *s)
{
	s->u.pc.ctr = 0xc;
	s->u.pc.ecr = 0x0;
}

static void parport_sunbpp_save_state(struct parport *p, struct parport_state *s)
{
	s->u.pc.ctr = parport_sunbpp_read_control(p);
}

static void parport_sunbpp_restore_state(struct parport *p, struct parport_state *s)
{
	parport_sunbpp_write_control(p, s->u.pc.ctr);
}

static struct parport_operations parport_sunbpp_ops = 
{
	.write_data	= parport_sunbpp_write_data,
	.read_data	= parport_sunbpp_read_data,

	.write_control	= parport_sunbpp_write_control,
	.read_control	= parport_sunbpp_read_control,
	.frob_control	= parport_sunbpp_frob_control,

	.read_status	= parport_sunbpp_read_status,

	.enable_irq	= parport_sunbpp_enable_irq,
	.disable_irq	= parport_sunbpp_disable_irq,

	.data_forward	= parport_sunbpp_data_forward,
	.data_reverse	= parport_sunbpp_data_reverse,

	.init_state	= parport_sunbpp_init_state,
	.save_state	= parport_sunbpp_save_state,
	.restore_state	= parport_sunbpp_restore_state,

	.epp_write_data	= parport_ieee1284_epp_write_data,
	.epp_read_data	= parport_ieee1284_epp_read_data,
	.epp_write_addr	= parport_ieee1284_epp_write_addr,
	.epp_read_addr	= parport_ieee1284_epp_read_addr,

	.ecp_write_data	= parport_ieee1284_ecp_write_data,
	.ecp_read_data	= parport_ieee1284_ecp_read_data,
	.ecp_write_addr	= parport_ieee1284_ecp_write_addr,

	.compat_write_data	= parport_ieee1284_write_compat,
	.nibble_read_data	= parport_ieee1284_read_nibble,
	.byte_read_data		= parport_ieee1284_read_byte,

	.owner		= THIS_MODULE,
};

static int bpp_probe(struct platform_device *op)
{
	struct parport_operations *ops;
	struct bpp_regs __iomem *regs;
	int irq, dma, err = 0, size;
	unsigned char value_tcr;
	void __iomem *base;
	struct parport *p;

	irq = op->archdata.irqs[0];
	base = of_ioremap(&op->resource[0], 0,
			  resource_size(&op->resource[0]),
			  "sunbpp");
	if (!base)
		return -ENODEV;

	size = resource_size(&op->resource[0]);
	dma = PARPORT_DMA_NONE;

	ops = kmemdup(&parport_sunbpp_ops, sizeof(struct parport_operations),
		      GFP_KERNEL);
        if (!ops)
		goto out_unmap;

	dprintk(("register_port\n"));
	if (!(p = parport_register_port((unsigned long)base, irq, dma, ops)))
		goto out_free_ops;

	p->size = size;
	p->dev = &op->dev;

	if ((err = request_irq(p->irq, parport_irq_handler,
			       IRQF_SHARED, p->name, p)) != 0) {
		goto out_put_port;
	}

	parport_sunbpp_enable_irq(p);

	regs = (struct bpp_regs __iomem *)p->base;

	value_tcr = sbus_readb(&regs->p_tcr);
	value_tcr &= ~P_TCR_DIR;
	sbus_writeb(value_tcr, &regs->p_tcr);

	printk(KERN_INFO "%s: sunbpp at 0x%lx\n", p->name, p->base);

	dev_set_drvdata(&op->dev, p);

	parport_announce_port(p);

	return 0;

out_put_port:
	parport_put_port(p);

out_free_ops:
	kfree(ops);

out_unmap:
	of_iounmap(&op->resource[0], base, size);

	return err;
}

static int bpp_remove(struct platform_device *op)
{
	struct parport *p = dev_get_drvdata(&op->dev);
	struct parport_operations *ops = p->ops;

	parport_remove_port(p);

	if (p->irq != PARPORT_IRQ_NONE) {
		parport_sunbpp_disable_irq(p);
		free_irq(p->irq, p);
	}

	of_iounmap(&op->resource[0], (void __iomem *) p->base, p->size);
	parport_put_port(p);
	kfree(ops);

	dev_set_drvdata(&op->dev, NULL);

	return 0;
}

static const struct of_device_id bpp_match[] = {
	{
		.name = "SUNW,bpp",
	},
	{},
};

MODULE_DEVICE_TABLE(of, bpp_match);

static struct platform_driver bpp_sbus_driver = {
	.driver = {
		.name = "bpp",
		.of_match_table = bpp_match,
	},
	.probe		= bpp_probe,
	.remove		= bpp_remove,
};

module_platform_driver(bpp_sbus_driver);

MODULE_AUTHOR("Derrick J Brashear");
MODULE_DESCRIPTION("Parport Driver for Sparc bidirectional Port");
MODULE_SUPPORTED_DEVICE("Sparc Bidirectional Parallel Port");
MODULE_VERSION("2.0");
MODULE_LICENSE("GPL");

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