^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) * SPI slave handler controlling system state
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) * This SPI slave handler allows remote control of system reboot, power off,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * halt, and suspend.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) * Copyright (C) 2016-2017 Glider bvba
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) * This file is subject to the terms and conditions of the GNU General Public
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) * License. See the file "COPYING" in the main directory of this archive
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) * for more details.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) * Usage (assuming /dev/spidev2.0 corresponds to the SPI master on the remote
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) * system):
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) * # reboot='\x7c\x50'
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) * # poweroff='\x71\x3f'
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) * # halt='\x38\x76'
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) * # suspend='\x1b\x1b'
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) * # spidev_test -D /dev/spidev2.0 -p $suspend # or $reboot, $poweroff, $halt
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) #include <linux/completion.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) #include <linux/reboot.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) #include <linux/suspend.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) #include <linux/spi/spi.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) * The numbers are chosen to display something human-readable on two 7-segment
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) * displays connected to two 74HC595 shift registers
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) #define CMD_REBOOT 0x7c50 /* rb */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) #define CMD_POWEROFF 0x713f /* OF */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) #define CMD_HALT 0x3876 /* HL */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) #define CMD_SUSPEND 0x1b1b /* ZZ */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) struct spi_slave_system_control_priv {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) struct spi_device *spi;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) struct completion finished;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) struct spi_transfer xfer;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) struct spi_message msg;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) __be16 cmd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) static
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) int spi_slave_system_control_submit(struct spi_slave_system_control_priv *priv);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) static void spi_slave_system_control_complete(void *arg)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) struct spi_slave_system_control_priv *priv = arg;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) u16 cmd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) if (priv->msg.status)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) goto terminate;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) cmd = be16_to_cpu(priv->cmd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) switch (cmd) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) case CMD_REBOOT:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) dev_info(&priv->spi->dev, "Rebooting system...\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) kernel_restart(NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) case CMD_POWEROFF:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) dev_info(&priv->spi->dev, "Powering off system...\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) kernel_power_off();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) case CMD_HALT:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) dev_info(&priv->spi->dev, "Halting system...\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) kernel_halt();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) case CMD_SUSPEND:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) dev_info(&priv->spi->dev, "Suspending system...\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) pm_suspend(PM_SUSPEND_MEM);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) default:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) dev_warn(&priv->spi->dev, "Unknown command 0x%x\n", cmd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) ret = spi_slave_system_control_submit(priv);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) goto terminate;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) terminate:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) dev_info(&priv->spi->dev, "Terminating\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) complete(&priv->finished);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) static
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) int spi_slave_system_control_submit(struct spi_slave_system_control_priv *priv)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) spi_message_init_with_transfers(&priv->msg, &priv->xfer, 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) priv->msg.complete = spi_slave_system_control_complete;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) priv->msg.context = priv;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) ret = spi_async(priv->spi, &priv->msg);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) dev_err(&priv->spi->dev, "spi_async() failed %d\n", ret);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) static int spi_slave_system_control_probe(struct spi_device *spi)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) struct spi_slave_system_control_priv *priv;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) priv = devm_kzalloc(&spi->dev, sizeof(*priv), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) if (!priv)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) priv->spi = spi;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) init_completion(&priv->finished);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) priv->xfer.rx_buf = &priv->cmd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) priv->xfer.len = sizeof(priv->cmd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) ret = spi_slave_system_control_submit(priv);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) spi_set_drvdata(spi, priv);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) static int spi_slave_system_control_remove(struct spi_device *spi)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) struct spi_slave_system_control_priv *priv = spi_get_drvdata(spi);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) spi_slave_abort(spi);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) wait_for_completion(&priv->finished);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) static struct spi_driver spi_slave_system_control_driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) .driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) .name = "spi-slave-system-control",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) .probe = spi_slave_system_control_probe,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) .remove = spi_slave_system_control_remove,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) module_spi_driver(spi_slave_system_control_driver);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) MODULE_AUTHOR("Geert Uytterhoeven <geert+renesas@glider.be>");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) MODULE_DESCRIPTION("SPI slave handler controlling system state");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) MODULE_LICENSE("GPL v2");
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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