Tom Rini | 83d290c | 2018-05-06 17:58:06 -0400 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0+ |
Hung-ying Tyan | f3424c5 | 2013-05-15 18:27:30 +0800 | [diff] [blame] | 2 | /* |
| 3 | * Chromium OS cros_ec driver - SPI interface |
| 4 | * |
| 5 | * Copyright (c) 2012 The Chromium OS Authors. |
Hung-ying Tyan | f3424c5 | 2013-05-15 18:27:30 +0800 | [diff] [blame] | 6 | */ |
| 7 | |
| 8 | /* |
| 9 | * The Matrix Keyboard Protocol driver handles talking to the keyboard |
| 10 | * controller chip. Mostly this is for keyboard functions, but some other |
| 11 | * things have slipped in, so we provide generic services to talk to the |
| 12 | * KBC. |
| 13 | */ |
| 14 | |
| 15 | #include <common.h> |
| 16 | #include <cros_ec.h> |
Simon Glass | ea0ebc8 | 2014-10-13 23:42:16 -0600 | [diff] [blame] | 17 | #include <dm.h> |
| 18 | #include <errno.h> |
Hung-ying Tyan | f3424c5 | 2013-05-15 18:27:30 +0800 | [diff] [blame] | 19 | #include <spi.h> |
| 20 | |
Simon Glass | ea0ebc8 | 2014-10-13 23:42:16 -0600 | [diff] [blame] | 21 | int cros_ec_spi_packet(struct udevice *udev, int out_bytes, int in_bytes) |
| 22 | { |
Simon Glass | e564f05 | 2015-03-05 12:25:20 -0700 | [diff] [blame] | 23 | struct cros_ec_dev *dev = dev_get_uclass_priv(udev); |
Simon Glass | bcbe3d1 | 2015-09-28 23:32:01 -0600 | [diff] [blame] | 24 | struct spi_slave *slave = dev_get_parent_priv(dev->dev); |
Simon Glass | 527265d | 2015-02-17 15:29:37 -0700 | [diff] [blame] | 25 | ulong start; |
| 26 | uint8_t byte; |
Randall Spangler | a607028 | 2014-02-27 13:26:10 -0700 | [diff] [blame] | 27 | int rv; |
| 28 | |
| 29 | /* Do the transfer */ |
Simon Glass | ea0ebc8 | 2014-10-13 23:42:16 -0600 | [diff] [blame] | 30 | if (spi_claim_bus(slave)) { |
Randall Spangler | a607028 | 2014-02-27 13:26:10 -0700 | [diff] [blame] | 31 | debug("%s: Cannot claim SPI bus\n", __func__); |
| 32 | return -1; |
| 33 | } |
| 34 | |
Simon Glass | 527265d | 2015-02-17 15:29:37 -0700 | [diff] [blame] | 35 | rv = spi_xfer(slave, out_bytes * 8, dev->dout, NULL, SPI_XFER_BEGIN); |
| 36 | if (rv) |
| 37 | goto done; |
| 38 | start = get_timer(0); |
| 39 | while (1) { |
| 40 | rv = spi_xfer(slave, 8, NULL, &byte, 0); |
| 41 | if (byte == SPI_PREAMBLE_END_BYTE) |
| 42 | break; |
| 43 | if (rv) |
| 44 | goto done; |
| 45 | if (get_timer(start) > 100) { |
| 46 | rv = -ETIMEDOUT; |
| 47 | goto done; |
| 48 | } |
| 49 | } |
Randall Spangler | a607028 | 2014-02-27 13:26:10 -0700 | [diff] [blame] | 50 | |
Simon Glass | 527265d | 2015-02-17 15:29:37 -0700 | [diff] [blame] | 51 | rv = spi_xfer(slave, in_bytes * 8, NULL, dev->din, 0); |
| 52 | done: |
| 53 | spi_xfer(slave, 0, NULL, NULL, SPI_XFER_END); |
Simon Glass | ea0ebc8 | 2014-10-13 23:42:16 -0600 | [diff] [blame] | 54 | spi_release_bus(slave); |
Randall Spangler | a607028 | 2014-02-27 13:26:10 -0700 | [diff] [blame] | 55 | |
| 56 | if (rv) { |
| 57 | debug("%s: Cannot complete SPI transfer\n", __func__); |
| 58 | return -1; |
| 59 | } |
| 60 | |
| 61 | return in_bytes; |
| 62 | } |
| 63 | |
Hung-ying Tyan | f3424c5 | 2013-05-15 18:27:30 +0800 | [diff] [blame] | 64 | /** |
| 65 | * Send a command to a LPC CROS_EC device and return the reply. |
| 66 | * |
| 67 | * The device's internal input/output buffers are used. |
| 68 | * |
| 69 | * @param dev CROS_EC device |
| 70 | * @param cmd Command to send (EC_CMD_...) |
| 71 | * @param cmd_version Version of command to send (EC_VER_...) |
| 72 | * @param dout Output data (may be NULL If dout_len=0) |
| 73 | * @param dout_len Size of output data in bytes |
| 74 | * @param dinp Returns pointer to response data. This will be |
| 75 | * untouched unless we return a value > 0. |
| 76 | * @param din_len Maximum size of response in bytes |
| 77 | * @return number of bytes in response, or -1 on error |
| 78 | */ |
Simon Glass | ea0ebc8 | 2014-10-13 23:42:16 -0600 | [diff] [blame] | 79 | int cros_ec_spi_command(struct udevice *udev, uint8_t cmd, int cmd_version, |
| 80 | const uint8_t *dout, int dout_len, |
| 81 | uint8_t **dinp, int din_len) |
| 82 | { |
Simon Glass | e564f05 | 2015-03-05 12:25:20 -0700 | [diff] [blame] | 83 | struct cros_ec_dev *dev = dev_get_uclass_priv(udev); |
Simon Glass | bcbe3d1 | 2015-09-28 23:32:01 -0600 | [diff] [blame] | 84 | struct spi_slave *slave = dev_get_parent_priv(dev->dev); |
Hung-ying Tyan | f3424c5 | 2013-05-15 18:27:30 +0800 | [diff] [blame] | 85 | int in_bytes = din_len + 4; /* status, length, checksum, trailer */ |
| 86 | uint8_t *out; |
| 87 | uint8_t *p; |
| 88 | int csum, len; |
| 89 | int rv; |
| 90 | |
Randall Spangler | e8c1266 | 2014-02-27 13:26:08 -0700 | [diff] [blame] | 91 | if (dev->protocol_version != 2) { |
| 92 | debug("%s: Unsupported EC protcol version %d\n", |
| 93 | __func__, dev->protocol_version); |
| 94 | return -1; |
| 95 | } |
| 96 | |
Hung-ying Tyan | f3424c5 | 2013-05-15 18:27:30 +0800 | [diff] [blame] | 97 | /* |
| 98 | * Sanity-check input size to make sure it plus transaction overhead |
| 99 | * fits in the internal device buffer. |
| 100 | */ |
| 101 | if (in_bytes > sizeof(dev->din)) { |
| 102 | debug("%s: Cannot receive %d bytes\n", __func__, din_len); |
| 103 | return -1; |
| 104 | } |
| 105 | |
| 106 | /* We represent message length as a byte */ |
| 107 | if (dout_len > 0xff) { |
| 108 | debug("%s: Cannot send %d bytes\n", __func__, dout_len); |
| 109 | return -1; |
| 110 | } |
| 111 | |
| 112 | /* |
| 113 | * Clear input buffer so we don't get false hits for MSG_HEADER |
| 114 | */ |
| 115 | memset(dev->din, '\0', in_bytes); |
| 116 | |
Simon Glass | ea0ebc8 | 2014-10-13 23:42:16 -0600 | [diff] [blame] | 117 | if (spi_claim_bus(slave)) { |
Hung-ying Tyan | f3424c5 | 2013-05-15 18:27:30 +0800 | [diff] [blame] | 118 | debug("%s: Cannot claim SPI bus\n", __func__); |
| 119 | return -1; |
| 120 | } |
| 121 | |
| 122 | out = dev->dout; |
Simon Glass | 2001b9a | 2014-07-07 10:16:37 -0600 | [diff] [blame] | 123 | out[0] = EC_CMD_VERSION0 + cmd_version; |
Hung-ying Tyan | f3424c5 | 2013-05-15 18:27:30 +0800 | [diff] [blame] | 124 | out[1] = cmd; |
| 125 | out[2] = (uint8_t)dout_len; |
| 126 | memcpy(out + 3, dout, dout_len); |
| 127 | csum = cros_ec_calc_checksum(out, 3) |
| 128 | + cros_ec_calc_checksum(dout, dout_len); |
| 129 | out[3 + dout_len] = (uint8_t)csum; |
| 130 | |
| 131 | /* |
| 132 | * Send output data and receive input data starting such that the |
| 133 | * message body will be dword aligned. |
| 134 | */ |
| 135 | p = dev->din + sizeof(int64_t) - 2; |
| 136 | len = dout_len + 4; |
| 137 | cros_ec_dump_data("out", cmd, out, len); |
Simon Glass | ea0ebc8 | 2014-10-13 23:42:16 -0600 | [diff] [blame] | 138 | rv = spi_xfer(slave, max(len, in_bytes) * 8, out, p, |
Hung-ying Tyan | f3424c5 | 2013-05-15 18:27:30 +0800 | [diff] [blame] | 139 | SPI_XFER_BEGIN | SPI_XFER_END); |
| 140 | |
Simon Glass | ea0ebc8 | 2014-10-13 23:42:16 -0600 | [diff] [blame] | 141 | spi_release_bus(slave); |
Hung-ying Tyan | f3424c5 | 2013-05-15 18:27:30 +0800 | [diff] [blame] | 142 | |
| 143 | if (rv) { |
| 144 | debug("%s: Cannot complete SPI transfer\n", __func__); |
| 145 | return -1; |
| 146 | } |
| 147 | |
Masahiro Yamada | b414119 | 2014-11-07 03:03:31 +0900 | [diff] [blame] | 148 | len = min((int)p[1], din_len); |
Hung-ying Tyan | f3424c5 | 2013-05-15 18:27:30 +0800 | [diff] [blame] | 149 | cros_ec_dump_data("in", -1, p, len + 3); |
| 150 | |
| 151 | /* Response code is first byte of message */ |
| 152 | if (p[0] != EC_RES_SUCCESS) { |
| 153 | printf("%s: Returned status %d\n", __func__, p[0]); |
| 154 | return -(int)(p[0]); |
| 155 | } |
| 156 | |
| 157 | /* Check checksum */ |
| 158 | csum = cros_ec_calc_checksum(p, len + 2); |
| 159 | if (csum != p[len + 2]) { |
| 160 | debug("%s: Invalid checksum rx %#02x, calced %#02x\n", __func__, |
| 161 | p[2 + len], csum); |
| 162 | return -1; |
| 163 | } |
| 164 | |
| 165 | /* Anything else is the response data */ |
| 166 | *dinp = p + 2; |
| 167 | |
| 168 | return len; |
| 169 | } |
| 170 | |
Simon Glass | b2568f0 | 2015-01-25 08:27:19 -0700 | [diff] [blame] | 171 | static int cros_ec_probe(struct udevice *dev) |
Simon Glass | ea0ebc8 | 2014-10-13 23:42:16 -0600 | [diff] [blame] | 172 | { |
Simon Glass | ea0ebc8 | 2014-10-13 23:42:16 -0600 | [diff] [blame] | 173 | return cros_ec_register(dev); |
| 174 | } |
| 175 | |
Simon Glass | b2568f0 | 2015-01-25 08:27:19 -0700 | [diff] [blame] | 176 | static struct dm_cros_ec_ops cros_ec_ops = { |
Simon Glass | ea0ebc8 | 2014-10-13 23:42:16 -0600 | [diff] [blame] | 177 | .packet = cros_ec_spi_packet, |
| 178 | .command = cros_ec_spi_command, |
| 179 | }; |
| 180 | |
| 181 | static const struct udevice_id cros_ec_ids[] = { |
Simon Glass | 3fbb787 | 2015-03-26 09:29:39 -0600 | [diff] [blame] | 182 | { .compatible = "google,cros-ec-spi" }, |
Simon Glass | ea0ebc8 | 2014-10-13 23:42:16 -0600 | [diff] [blame] | 183 | { } |
| 184 | }; |
| 185 | |
| 186 | U_BOOT_DRIVER(cros_ec_spi) = { |
Simon Glass | 3fbb787 | 2015-03-26 09:29:39 -0600 | [diff] [blame] | 187 | .name = "cros_ec_spi", |
Simon Glass | ea0ebc8 | 2014-10-13 23:42:16 -0600 | [diff] [blame] | 188 | .id = UCLASS_CROS_EC, |
| 189 | .of_match = cros_ec_ids, |
| 190 | .probe = cros_ec_probe, |
| 191 | .ops = &cros_ec_ops, |
| 192 | }; |