1 // SPDX-License-Identifier: GPL-2.0-only
9 #include "mipi-phy.h"
12  * Default D-PHY timings based on MIPI D-PHY specification. Derived from the
13  * valid ranges specified in Section 6.9, Table 14, Page 40 of the D-PHY
19 	timing->clkmiss = 0;  in mipi_dphy_timing_get_default()
20 	timing->clkpost = 70 + 52 * period;  in mipi_dphy_timing_get_default()
21 	timing->clkpre = 8;  in mipi_dphy_timing_get_default()
22 	timing->clkprepare = 65;  in mipi_dphy_timing_get_default()
23 	timing->clksettle = 95;  in mipi_dphy_timing_get_default()
24 	timing->clktermen = 0;  in mipi_dphy_timing_get_default()
25 	timing->clktrail = 80;  in mipi_dphy_timing_get_default()
26 	timing->clkzero = 260;  in mipi_dphy_timing_get_default()
27 	timing->dtermen = 0;  in mipi_dphy_timing_get_default()
28 	timing->eot = 0;  in mipi_dphy_timing_get_default()
29 	timing->hsexit = 120;  in mipi_dphy_timing_get_default()
30 	timing->hsprepare = 65 + 5 * period;  in mipi_dphy_timing_get_default()
31 	timing->hszero = 145 + 5 * period;  in mipi_dphy_timing_get_default()
32 	timing->hssettle = 85 + 6 * period;  in mipi_dphy_timing_get_default()
33 	timing->hsskip = 40;  in mipi_dphy_timing_get_default()
36 	 * The MIPI D-PHY specification (Section 6.9, v1.2, Table 14, Page 40)  in mipi_dphy_timing_get_default()
39 	 *     T_HS-TRAIL = max(n * 8 * period, 60 + n * 4 * period)  in mipi_dphy_timing_get_default()
41 	 * where n = 1 for forward-direction HS mode and n = 4 for reverse-  in mipi_dphy_timing_get_default()
42 	 * direction HS mode. There's only one setting and this function does  in mipi_dphy_timing_get_default()
44 	 * assumes that reverse-direction HS mode is supported and uses n = 4.  in mipi_dphy_timing_get_default()
46 	timing->hstrail = max(4 * 8 * period, 60 + 4 * 4 * period);  in mipi_dphy_timing_get_default()
48 	timing->init = 100000;  in mipi_dphy_timing_get_default()
49 	timing->lpx = 60;  in mipi_dphy_timing_get_default()
50 	timing->taget = 5 * timing->lpx;  in mipi_dphy_timing_get_default()
51 	timing->tago = 4 * timing->lpx;  in mipi_dphy_timing_get_default()
52 	timing->tasure = 2 * timing->lpx;  in mipi_dphy_timing_get_default()
53 	timing->wakeup = 1000000;  in mipi_dphy_timing_get_default()
59  * Validate D-PHY timing according to MIPI D-PHY specification (v1.2, Section
65 	if (timing->clkmiss > 60)  in mipi_dphy_timing_validate()
66 		return -EINVAL;  in mipi_dphy_timing_validate()
68 	if (timing->clkpost < (60 + 52 * period))  in mipi_dphy_timing_validate()
69 		return -EINVAL;  in mipi_dphy_timing_validate()
71 	if (timing->clkpre < 8)  in mipi_dphy_timing_validate()
72 		return -EINVAL;  in mipi_dphy_timing_validate()
74 	if (timing->clkprepare < 38 || timing->clkprepare > 95)  in mipi_dphy_timing_validate()
75 		return -EINVAL;  in mipi_dphy_timing_validate()
77 	if (timing->clksettle < 95 || timing->clksettle > 300)  in mipi_dphy_timing_validate()
78 		return -EINVAL;  in mipi_dphy_timing_validate()
80 	if (timing->clktermen > 38)  in mipi_dphy_timing_validate()
81 		return -EINVAL;  in mipi_dphy_timing_validate()
83 	if (timing->clktrail < 60)  in mipi_dphy_timing_validate()
84 		return -EINVAL;  in mipi_dphy_timing_validate()
86 	if (timing->clkprepare + timing->clkzero < 300)  in mipi_dphy_timing_validate()
87 		return -EINVAL;  in mipi_dphy_timing_validate()
89 	if (timing->dtermen > 35 + 4 * period)  in mipi_dphy_timing_validate()
90 		return -EINVAL;  in mipi_dphy_timing_validate()
92 	if (timing->eot > 105 + 12 * period)  in mipi_dphy_timing_validate()
93 		return -EINVAL;  in mipi_dphy_timing_validate()
95 	if (timing->hsexit < 100)  in mipi_dphy_timing_validate()
96 		return -EINVAL;  in mipi_dphy_timing_validate()
98 	if (timing->hsprepare < 40 + 4 * period ||  in mipi_dphy_timing_validate()
99 	    timing->hsprepare > 85 + 6 * period)  in mipi_dphy_timing_validate()
100 		return -EINVAL;  in mipi_dphy_timing_validate()
102 	if (timing->hsprepare + timing->hszero < 145 + 10 * period)  in mipi_dphy_timing_validate()
103 		return -EINVAL;  in mipi_dphy_timing_validate()
105 	if ((timing->hssettle < 85 + 6 * period) ||  in mipi_dphy_timing_validate()
106 	    (timing->hssettle > 145 + 10 * period))  in mipi_dphy_timing_validate()
107 		return -EINVAL;  in mipi_dphy_timing_validate()
109 	if (timing->hsskip < 40 || timing->hsskip > 55 + 4 * period)  in mipi_dphy_timing_validate()
110 		return -EINVAL;  in mipi_dphy_timing_validate()
112 	if (timing->hstrail < max(8 * period, 60 + 4 * period))  in mipi_dphy_timing_validate()
113 		return -EINVAL;  in mipi_dphy_timing_validate()
115 	if (timing->init < 100000)  in mipi_dphy_timing_validate()
116 		return -EINVAL;  in mipi_dphy_timing_validate()
118 	if (timing->lpx < 50)  in mipi_dphy_timing_validate()
119 		return -EINVAL;  in mipi_dphy_timing_validate()
121 	if (timing->taget != 5 * timing->lpx)  in mipi_dphy_timing_validate()
122 		return -EINVAL;  in mipi_dphy_timing_validate()
124 	if (timing->tago != 4 * timing->lpx)  in mipi_dphy_timing_validate()
125 		return -EINVAL;  in mipi_dphy_timing_validate()
127 	if (timing->tasure < timing->lpx || timing->tasure > 2 * timing->lpx)  in mipi_dphy_timing_validate()
128 		return -EINVAL;  in mipi_dphy_timing_validate()
130 	if (timing->wakeup < 1000000)  in mipi_dphy_timing_validate()
131 		return -EINVAL;  in mipi_dphy_timing_validate()