1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * DaVinci pinmux functions.
4 *
5 * Copyright (C) 2009 Nick Thompson, GE Fanuc Ltd, <nick.thompson@gefanuc.com>
6 * Copyright (C) 2007 Sergey Kubushyn <ksi@koi8.net>
7 * Copyright (C) 2008 Lyrtech <www.lyrtech.com>
8 * Copyright (C) 2004 Texas Instruments.
9 */
10
11 #include <common.h>
12 #include <asm/arch/hardware.h>
13 #include <asm/io.h>
14 #include <asm/arch/davinci_misc.h>
15
16 /*
17 * Change the setting of a pin multiplexer field.
18 *
19 * Takes an array of pinmux settings similar to:
20 *
21 * struct pinmux_config uart_pins[] = {
22 * { &davinci_syscfg_regs->pinmux[8], 2, 7 },
23 * { &davinci_syscfg_regs->pinmux[9], 2, 0 }
24 * };
25 *
26 * Stepping through the array, each pinmux[n] register has the given value
27 * set in the pin mux field specified.
28 *
29 * The number of pins in the array must be passed (ARRAY_SIZE can provide
30 * this value conveniently).
31 *
32 * Returns 0 if all field numbers and values are in the correct range,
33 * else returns -1.
34 */
davinci_configure_pin_mux(const struct pinmux_config * pins,const int n_pins)35 int davinci_configure_pin_mux(const struct pinmux_config *pins,
36 const int n_pins)
37 {
38 int i;
39
40 /* check for invalid pinmux values */
41 for (i = 0; i < n_pins; i++) {
42 if (pins[i].field >= PIN_MUX_NUM_FIELDS ||
43 (pins[i].value & ~PIN_MUX_FIELD_MASK) != 0)
44 return -1;
45 }
46
47 /* configure the pinmuxes */
48 for (i = 0; i < n_pins; i++) {
49 const int offset = pins[i].field * PIN_MUX_FIELD_SIZE;
50 const unsigned int value = pins[i].value << offset;
51 const unsigned int mask = PIN_MUX_FIELD_MASK << offset;
52 const dv_reg *mux = pins[i].mux;
53
54 writel(value | (readl(mux) & (~mask)), mux);
55 }
56
57 return 0;
58 }
59
60 /*
61 * Configure multiple pinmux resources.
62 *
63 * Takes an pinmux_resource array of pinmux_config and pin counts:
64 *
65 * const struct pinmux_resource pinmuxes[] = {
66 * PINMUX_ITEM(uart_pins),
67 * PINMUX_ITEM(i2c_pins),
68 * };
69 *
70 * The number of items in the array must be passed (ARRAY_SIZE can provide
71 * this value conveniently).
72 *
73 * Each item entry is configured in the defined order. If configuration
74 * of any item fails, -1 is returned and none of the following items are
75 * configured. On success, 0 is returned.
76 */
davinci_configure_pin_mux_items(const struct pinmux_resource * item,const int n_items)77 int davinci_configure_pin_mux_items(const struct pinmux_resource *item,
78 const int n_items)
79 {
80 int i;
81
82 for (i = 0; i < n_items; i++) {
83 if (davinci_configure_pin_mux(item[i].pins,
84 item[i].n_pins) != 0)
85 return -1;
86 }
87
88 return 0;
89 }
90