linux/drivers/media/video/isp/ispcsiphy.c

/*
 * ispcsiphy.c
 *
 * TI OMAP3 ISP - CSI PHY module
 *
 * Copyright (C) 2010 Nokia Corporation
 * Copyright (C) 2009 Texas Instruments, Inc.
 *
 * Contacts: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
 *	     Sakari Ailus <sakari.ailus@maxwell.research.nokia.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 */

#include <linux/delay.h>
#include <linux/device.h>
#include <linux/regulator/consumer.h>

#include "isp.h"
#include "ispreg.h"
#include "ispcsiphy.h"

/*
 * csiphy_lanes_config - Configuration of CSIPHY lanes.
 *
 * Updates HW configuration.
 * Called with phy->mutex taken.
 */
static void csiphy_lanes_config(struct isp_csiphy *phy)
{
	unsigned int i;
	u32 reg;

	reg = isp_reg_readl(phy->isp, phy->cfg_regs, ISPCSI2_PHY_CFG);

	for (i = 0; i < phy->num_data_lanes; i++) {
		reg &= ~(ISPCSI2_PHY_CFG_DATA_POL_MASK(i + 1) |
			 ISPCSI2_PHY_CFG_DATA_POSITION_MASK(i + 1));
		reg |= (phy->lanes.data[i].pol <<
			ISPCSI2_PHY_CFG_DATA_POL_SHIFT(i + 1));
		reg |= (phy->lanes.data[i].pos <<
			ISPCSI2_PHY_CFG_DATA_POSITION_SHIFT(i + 1));
	}

	reg &= ~(ISPCSI2_PHY_CFG_CLOCK_POL_MASK |
		 ISPCSI2_PHY_CFG_CLOCK_POSITION_MASK);
	reg |= phy->lanes.clk.pol << ISPCSI2_PHY_CFG_CLOCK_POL_SHIFT;
	reg |= phy->lanes.clk.pos << ISPCSI2_PHY_CFG_CLOCK_POSITION_SHIFT;

	isp_reg_writel(phy->isp, reg, phy->cfg_regs, ISPCSI2_PHY_CFG);
}

/*
 * csiphy_power_autoswitch_enable
 * @enable: Sets or clears the autoswitch function enable flag.
 */
static void csiphy_power_autoswitch_enable(struct isp_csiphy *phy, bool enable)
{
	isp_reg_clr_set(phy->isp, phy->cfg_regs, ISPCSI2_PHY_CFG,
			ISPCSI2_PHY_CFG_PWR_AUTO,
			enable ? ISPCSI2_PHY_CFG_PWR_AUTO : 0);
}

/*
 * csiphy_set_power
 * @power: Power state to be set.
 *
 * Returns 0 if successful, or -EBUSY if the retry count is exceeded.
 */
static int csiphy_set_power(struct isp_csiphy *phy, u32 power)
{
	u32 reg;
	u8 retry_count;

	isp_reg_clr_set(phy->isp, phy->cfg_regs, ISPCSI2_PHY_CFG,
			ISPCSI2_PHY_CFG_PWR_CMD_MASK, power);

	retry_count = 0;
	do {
		udelay(50);
		reg = isp_reg_readl(phy->isp, phy->cfg_regs, ISPCSI2_PHY_CFG) &
				    ISPCSI2_PHY_CFG_PWR_STATUS_MASK;

		if (reg != power >> 2)
			retry_count++;

	} while ((reg != power >> 2) && (retry_count < 100));

	if (retry_count == 100) {
		printk(KERN_ERR "CSI2 CIO set power failed!\n");
		return -EBUSY;
	}

	return 0;
}

/*
 * csiphy_dphy_config - Configure CSI2 D-PHY parameters.
 *
 * Called with phy->mutex taken.
 */
static void csiphy_dphy_config(struct isp_csiphy *phy)
{
	u32 reg;

	/* Set up ISPCSIPHY_REG0 */
	reg = isp_reg_readl(phy->isp, phy->phy_regs, ISPCSIPHY_REG0);

	reg &= ~(ISPCSIPHY_REG0_THS_TERM_MASK |
		 ISPCSIPHY_REG0_THS_SETTLE_MASK);
	reg |= phy->dphy.ths_term << ISPCSIPHY_REG0_THS_TERM_SHIFT;
	reg |= phy->dphy.ths_settle << ISPCSIPHY_REG0_THS_SETTLE_SHIFT;

	isp_reg_writel(phy->isp, reg, phy->phy_regs, ISPCSIPHY_REG0);

	/* Set up ISPCSIPHY_REG1 */
	reg = isp_reg_readl(phy->isp, phy->phy_regs, ISPCSIPHY_REG1);

	reg &= ~(ISPCSIPHY_REG1_TCLK_TERM_MASK |
		 ISPCSIPHY_REG1_TCLK_MISS_MASK |
		 ISPCSIPHY_REG1_TCLK_SETTLE_MASK);
	reg |= phy->dphy.tclk_term << ISPCSIPHY_REG1_TCLK_TERM_SHIFT;
	reg |= phy->dphy.tclk_miss << ISPCSIPHY_REG1_TCLK_MISS_SHIFT;
	reg |= phy->dphy.tclk_settle << ISPCSIPHY_REG1_TCLK_SETTLE_SHIFT;

	isp_reg_writel(phy->isp, reg, phy->phy_regs, ISPCSIPHY_REG1);
}

static int isp_csiphy_config(struct isp_csiphy *phy,
			     struct isp_csiphy_dphy_cfg *dphy,
			     struct isp_csiphy_lanes_cfg *lanes)
{
	unsigned int used_lanes = 0;
	unsigned int i;

	/* Clock and data lanes verification */
	for (i = 0; i < phy->num_data_lanes; i++) {
		if (lanes->data[i].pol > 1 || lanes->data[i].pos > 3)
			return -EINVAL;

		if (used_lanes & (1 << lanes->data[i].pos))
			return -EINVAL;

		used_lanes |= 1 << lanes->data[i].pos;
	}

	if (lanes->clk.pol > 1 || lanes->clk.pos > 3)
		return -EINVAL;

	if (lanes->clk.pos == 0 || used_lanes & (1 << lanes->clk.pos))
		return -EINVAL;

	mutex_lock(&phy->mutex);
	phy->dphy = *dphy;
	phy->lanes = *lanes;
	mutex_unlock(&phy->mutex);

	return 0;
}

int isp_csiphy_acquire(struct isp_csiphy *phy)
{
	int rval;

	if (phy->vdd == NULL) {
		dev_err(phy->isp->dev, "Power regulator for CSI PHY not "
			"available\n");
		return -ENODEV;
	}

	mutex_lock(&phy->mutex);

	rval = regulator_enable(phy->vdd);
	if (rval < 0)
		goto done;

	isp_csi2_reset(phy->csi2);

	csiphy_dphy_config(phy);
	csiphy_lanes_config(phy);

	rval = csiphy_set_power(phy, ISPCSI2_PHY_CFG_PWR_CMD_ON);
	if (rval) {
		regulator_disable(phy->vdd);
		goto done;
	}

	csiphy_power_autoswitch_enable(phy, true);
	phy->phy_in_use = 1;

done:
	mutex_unlock(&phy->mutex);
	return rval;
}

void isp_csiphy_release(struct isp_csiphy *phy)
{
	mutex_lock(&phy->mutex);
	if (phy->phy_in_use) {
		csiphy_power_autoswitch_enable(phy, false);
		csiphy_set_power(phy, ISPCSI2_PHY_CFG_PWR_CMD_OFF);
		regulator_disable(phy->vdd);
		phy->phy_in_use = 0;
	}
	mutex_unlock(&phy->mutex);
}

/*
 * isp_csiphy_init - Initialize the CSI PHY frontends
 */
int isp_csiphy_init(struct isp_device *isp)
{
	struct isp_csiphy *phy1 = &isp->isp_csiphy1;
	struct isp_csiphy *phy2 = &isp->isp_csiphy2;

	isp->platform_cb.csiphy_config = isp_csiphy_config;

	phy2->isp = isp;
	phy2->csi2 = &isp->isp_csi2a;
	phy2->num_data_lanes = ISP_CSIPHY2_NUM_DATA_LANES;
	phy2->cfg_regs = OMAP3_ISP_IOMEM_CSI2A_REGS1;
	phy2->phy_regs = OMAP3_ISP_IOMEM_CSIPHY2;
	mutex_init(&phy2->mutex);

	if (isp->revision == ISP_REVISION_15_0) {
		phy1->isp = isp;
		phy1->csi2 = &isp->isp_csi2c;
		phy1->num_data_lanes = ISP_CSIPHY1_NUM_DATA_LANES;
		phy1->cfg_regs = OMAP3_ISP_IOMEM_CSI2C_REGS1;
		phy1->phy_regs = OMAP3_ISP_IOMEM_CSIPHY1;
		mutex_init(&phy1->mutex);
	}

	return 0;
}