1 /*
2  * ispcsiphy.c
3  *
4  * TI OMAP3 ISP - CSI PHY module
5  *
6  * Copyright (C) 2010 Nokia Corporation
7  * Copyright (C) 2009 Texas Instruments, Inc.
8  *
9  * Contacts: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
10  *	     Sakari Ailus <sakari.ailus@iki.fi>
11  *
12  * This program is free software; you can redistribute it and/or modify
13  * it under the terms of the GNU General Public License version 2 as
14  * published by the Free Software Foundation.
15  *
16  * This program is distributed in the hope that it will be useful, but
17  * WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
19  * General Public License for more details.
20  *
21  * You should have received a copy of the GNU General Public License
22  * along with this program; if not, write to the Free Software
23  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
24  * 02110-1301 USA
25  */
26 
27 #include <linux/delay.h>
28 #include <linux/device.h>
29 #include <linux/regulator/consumer.h>
30 
31 #include "isp.h"
32 #include "ispreg.h"
33 #include "ispcsiphy.h"
34 
35 /*
36  * csiphy_lanes_config - Configuration of CSIPHY lanes.
37  *
38  * Updates HW configuration.
39  * Called with phy->mutex taken.
40  */
csiphy_lanes_config(struct isp_csiphy * phy)41 static void csiphy_lanes_config(struct isp_csiphy *phy)
42 {
43 	unsigned int i;
44 	u32 reg;
45 
46 	reg = isp_reg_readl(phy->isp, phy->cfg_regs, ISPCSI2_PHY_CFG);
47 
48 	for (i = 0; i < phy->num_data_lanes; i++) {
49 		reg &= ~(ISPCSI2_PHY_CFG_DATA_POL_MASK(i + 1) |
50 			 ISPCSI2_PHY_CFG_DATA_POSITION_MASK(i + 1));
51 		reg |= (phy->lanes.data[i].pol <<
52 			ISPCSI2_PHY_CFG_DATA_POL_SHIFT(i + 1));
53 		reg |= (phy->lanes.data[i].pos <<
54 			ISPCSI2_PHY_CFG_DATA_POSITION_SHIFT(i + 1));
55 	}
56 
57 	reg &= ~(ISPCSI2_PHY_CFG_CLOCK_POL_MASK |
58 		 ISPCSI2_PHY_CFG_CLOCK_POSITION_MASK);
59 	reg |= phy->lanes.clk.pol << ISPCSI2_PHY_CFG_CLOCK_POL_SHIFT;
60 	reg |= phy->lanes.clk.pos << ISPCSI2_PHY_CFG_CLOCK_POSITION_SHIFT;
61 
62 	isp_reg_writel(phy->isp, reg, phy->cfg_regs, ISPCSI2_PHY_CFG);
63 }
64 
65 /*
66  * csiphy_power_autoswitch_enable
67  * @enable: Sets or clears the autoswitch function enable flag.
68  */
csiphy_power_autoswitch_enable(struct isp_csiphy * phy,bool enable)69 static void csiphy_power_autoswitch_enable(struct isp_csiphy *phy, bool enable)
70 {
71 	isp_reg_clr_set(phy->isp, phy->cfg_regs, ISPCSI2_PHY_CFG,
72 			ISPCSI2_PHY_CFG_PWR_AUTO,
73 			enable ? ISPCSI2_PHY_CFG_PWR_AUTO : 0);
74 }
75 
76 /*
77  * csiphy_set_power
78  * @power: Power state to be set.
79  *
80  * Returns 0 if successful, or -EBUSY if the retry count is exceeded.
81  */
csiphy_set_power(struct isp_csiphy * phy,u32 power)82 static int csiphy_set_power(struct isp_csiphy *phy, u32 power)
83 {
84 	u32 reg;
85 	u8 retry_count;
86 
87 	isp_reg_clr_set(phy->isp, phy->cfg_regs, ISPCSI2_PHY_CFG,
88 			ISPCSI2_PHY_CFG_PWR_CMD_MASK, power);
89 
90 	retry_count = 0;
91 	do {
92 		udelay(50);
93 		reg = isp_reg_readl(phy->isp, phy->cfg_regs, ISPCSI2_PHY_CFG) &
94 				    ISPCSI2_PHY_CFG_PWR_STATUS_MASK;
95 
96 		if (reg != power >> 2)
97 			retry_count++;
98 
99 	} while ((reg != power >> 2) && (retry_count < 100));
100 
101 	if (retry_count == 100) {
102 		printk(KERN_ERR "CSI2 CIO set power failed!\n");
103 		return -EBUSY;
104 	}
105 
106 	return 0;
107 }
108 
109 /*
110  * csiphy_dphy_config - Configure CSI2 D-PHY parameters.
111  *
112  * Called with phy->mutex taken.
113  */
csiphy_dphy_config(struct isp_csiphy * phy)114 static void csiphy_dphy_config(struct isp_csiphy *phy)
115 {
116 	u32 reg;
117 
118 	/* Set up ISPCSIPHY_REG0 */
119 	reg = isp_reg_readl(phy->isp, phy->phy_regs, ISPCSIPHY_REG0);
120 
121 	reg &= ~(ISPCSIPHY_REG0_THS_TERM_MASK |
122 		 ISPCSIPHY_REG0_THS_SETTLE_MASK);
123 	reg |= phy->dphy.ths_term << ISPCSIPHY_REG0_THS_TERM_SHIFT;
124 	reg |= phy->dphy.ths_settle << ISPCSIPHY_REG0_THS_SETTLE_SHIFT;
125 
126 	isp_reg_writel(phy->isp, reg, phy->phy_regs, ISPCSIPHY_REG0);
127 
128 	/* Set up ISPCSIPHY_REG1 */
129 	reg = isp_reg_readl(phy->isp, phy->phy_regs, ISPCSIPHY_REG1);
130 
131 	reg &= ~(ISPCSIPHY_REG1_TCLK_TERM_MASK |
132 		 ISPCSIPHY_REG1_TCLK_MISS_MASK |
133 		 ISPCSIPHY_REG1_TCLK_SETTLE_MASK);
134 	reg |= phy->dphy.tclk_term << ISPCSIPHY_REG1_TCLK_TERM_SHIFT;
135 	reg |= phy->dphy.tclk_miss << ISPCSIPHY_REG1_TCLK_MISS_SHIFT;
136 	reg |= phy->dphy.tclk_settle << ISPCSIPHY_REG1_TCLK_SETTLE_SHIFT;
137 
138 	isp_reg_writel(phy->isp, reg, phy->phy_regs, ISPCSIPHY_REG1);
139 }
140 
csiphy_config(struct isp_csiphy * phy,struct isp_csiphy_dphy_cfg * dphy,struct isp_csiphy_lanes_cfg * lanes)141 static int csiphy_config(struct isp_csiphy *phy,
142 			 struct isp_csiphy_dphy_cfg *dphy,
143 			 struct isp_csiphy_lanes_cfg *lanes)
144 {
145 	unsigned int used_lanes = 0;
146 	unsigned int i;
147 
148 	/* Clock and data lanes verification */
149 	for (i = 0; i < phy->num_data_lanes; i++) {
150 		if (lanes->data[i].pol > 1 || lanes->data[i].pos > 3)
151 			return -EINVAL;
152 
153 		if (used_lanes & (1 << lanes->data[i].pos))
154 			return -EINVAL;
155 
156 		used_lanes |= 1 << lanes->data[i].pos;
157 	}
158 
159 	if (lanes->clk.pol > 1 || lanes->clk.pos > 3)
160 		return -EINVAL;
161 
162 	if (lanes->clk.pos == 0 || used_lanes & (1 << lanes->clk.pos))
163 		return -EINVAL;
164 
165 	mutex_lock(&phy->mutex);
166 	phy->dphy = *dphy;
167 	phy->lanes = *lanes;
168 	mutex_unlock(&phy->mutex);
169 
170 	return 0;
171 }
172 
omap3isp_csiphy_acquire(struct isp_csiphy * phy)173 int omap3isp_csiphy_acquire(struct isp_csiphy *phy)
174 {
175 	int rval;
176 
177 	if (phy->vdd == NULL) {
178 		dev_err(phy->isp->dev, "Power regulator for CSI PHY not "
179 			"available\n");
180 		return -ENODEV;
181 	}
182 
183 	mutex_lock(&phy->mutex);
184 
185 	rval = regulator_enable(phy->vdd);
186 	if (rval < 0)
187 		goto done;
188 
189 	omap3isp_csi2_reset(phy->csi2);
190 
191 	csiphy_dphy_config(phy);
192 	csiphy_lanes_config(phy);
193 
194 	rval = csiphy_set_power(phy, ISPCSI2_PHY_CFG_PWR_CMD_ON);
195 	if (rval) {
196 		regulator_disable(phy->vdd);
197 		goto done;
198 	}
199 
200 	csiphy_power_autoswitch_enable(phy, true);
201 	phy->phy_in_use = 1;
202 
203 done:
204 	mutex_unlock(&phy->mutex);
205 	return rval;
206 }
207 
omap3isp_csiphy_release(struct isp_csiphy * phy)208 void omap3isp_csiphy_release(struct isp_csiphy *phy)
209 {
210 	mutex_lock(&phy->mutex);
211 	if (phy->phy_in_use) {
212 		csiphy_power_autoswitch_enable(phy, false);
213 		csiphy_set_power(phy, ISPCSI2_PHY_CFG_PWR_CMD_OFF);
214 		regulator_disable(phy->vdd);
215 		phy->phy_in_use = 0;
216 	}
217 	mutex_unlock(&phy->mutex);
218 }
219 
220 /*
221  * omap3isp_csiphy_init - Initialize the CSI PHY frontends
222  */
omap3isp_csiphy_init(struct isp_device * isp)223 int omap3isp_csiphy_init(struct isp_device *isp)
224 {
225 	struct isp_csiphy *phy1 = &isp->isp_csiphy1;
226 	struct isp_csiphy *phy2 = &isp->isp_csiphy2;
227 
228 	isp->platform_cb.csiphy_config = csiphy_config;
229 
230 	phy2->isp = isp;
231 	phy2->csi2 = &isp->isp_csi2a;
232 	phy2->num_data_lanes = ISP_CSIPHY2_NUM_DATA_LANES;
233 	phy2->cfg_regs = OMAP3_ISP_IOMEM_CSI2A_REGS1;
234 	phy2->phy_regs = OMAP3_ISP_IOMEM_CSIPHY2;
235 	mutex_init(&phy2->mutex);
236 
237 	if (isp->revision == ISP_REVISION_15_0) {
238 		phy1->isp = isp;
239 		phy1->csi2 = &isp->isp_csi2c;
240 		phy1->num_data_lanes = ISP_CSIPHY1_NUM_DATA_LANES;
241 		phy1->cfg_regs = OMAP3_ISP_IOMEM_CSI2C_REGS1;
242 		phy1->phy_regs = OMAP3_ISP_IOMEM_CSIPHY1;
243 		mutex_init(&phy1->mutex);
244 	}
245 
246 	return 0;
247 }
248