1235783Skib/* 2235783Skib * Copyright �� 2009 Keith Packard 3235783Skib * 4235783Skib * Permission to use, copy, modify, distribute, and sell this software and its 5235783Skib * documentation for any purpose is hereby granted without fee, provided that 6235783Skib * the above copyright notice appear in all copies and that both that copyright 7235783Skib * notice and this permission notice appear in supporting documentation, and 8235783Skib * that the name of the copyright holders not be used in advertising or 9235783Skib * publicity pertaining to distribution of the software without specific, 10235783Skib * written prior permission. The copyright holders make no representations 11235783Skib * about the suitability of this software for any purpose. It is provided "as 12235783Skib * is" without express or implied warranty. 13235783Skib * 14235783Skib * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, 15235783Skib * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO 16235783Skib * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR 17235783Skib * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, 18235783Skib * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER 19235783Skib * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE 20235783Skib * OF THIS SOFTWARE. 21235783Skib */ 22235783Skib 23235783Skib#include <sys/cdefs.h> 24235783Skib__FBSDID("$FreeBSD$"); 25235783Skib 26298951Sjhb#include <sys/types.h> 27235783Skib#include <sys/kobj.h> 28235783Skib#include <sys/bus.h> 29268564Srpaulo#include <dev/iicbus/iic.h> 30235783Skib#include "iicbus_if.h" 31235783Skib#include <dev/iicbus/iiconf.h> 32235783Skib#include <dev/drm2/drmP.h> 33235783Skib#include <dev/drm2/drm_dp_helper.h> 34235783Skib 35235783Skibstatic int 36235783Skibiic_dp_aux_transaction(device_t idev, int mode, uint8_t write_byte, 37235783Skib uint8_t *read_byte) 38235783Skib{ 39235783Skib struct iic_dp_aux_data *aux_data; 40235783Skib int ret; 41235783Skib 42235783Skib aux_data = device_get_softc(idev); 43235783Skib ret = (*aux_data->aux_ch)(idev, mode, write_byte, read_byte); 44280183Sdumbbell if (ret < 0) 45280183Sdumbbell return (ret); 46280183Sdumbbell return (0); 47235783Skib} 48235783Skib 49235783Skib/* 50235783Skib * I2C over AUX CH 51235783Skib */ 52235783Skib 53235783Skib/* 54235783Skib * Send the address. If the I2C link is running, this 'restarts' 55235783Skib * the connection with the new address, this is used for doing 56235783Skib * a write followed by a read (as needed for DDC) 57235783Skib */ 58235783Skibstatic int 59235783Skibiic_dp_aux_address(device_t idev, u16 address, bool reading) 60235783Skib{ 61235783Skib struct iic_dp_aux_data *aux_data; 62235783Skib int mode, ret; 63235783Skib 64235783Skib aux_data = device_get_softc(idev); 65235783Skib mode = MODE_I2C_START; 66235783Skib if (reading) 67235783Skib mode |= MODE_I2C_READ; 68235783Skib else 69235783Skib mode |= MODE_I2C_WRITE; 70235783Skib aux_data->address = address; 71235783Skib aux_data->running = true; 72235783Skib ret = iic_dp_aux_transaction(idev, mode, 0, NULL); 73235783Skib return (ret); 74235783Skib} 75235783Skib 76235783Skib/* 77235783Skib * Stop the I2C transaction. This closes out the link, sending 78235783Skib * a bare address packet with the MOT bit turned off 79235783Skib */ 80235783Skibstatic void 81235783Skibiic_dp_aux_stop(device_t idev, bool reading) 82235783Skib{ 83235783Skib struct iic_dp_aux_data *aux_data; 84235783Skib int mode; 85235783Skib 86235783Skib aux_data = device_get_softc(idev); 87235783Skib mode = MODE_I2C_STOP; 88235783Skib if (reading) 89235783Skib mode |= MODE_I2C_READ; 90235783Skib else 91235783Skib mode |= MODE_I2C_WRITE; 92235783Skib if (aux_data->running) { 93235783Skib (void)iic_dp_aux_transaction(idev, mode, 0, NULL); 94235783Skib aux_data->running = false; 95235783Skib } 96235783Skib} 97235783Skib 98235783Skib/* 99235783Skib * Write a single byte to the current I2C address, the 100235783Skib * the I2C link must be running or this returns -EIO 101235783Skib */ 102235783Skibstatic int 103235783Skibiic_dp_aux_put_byte(device_t idev, u8 byte) 104235783Skib{ 105235783Skib struct iic_dp_aux_data *aux_data; 106235783Skib int ret; 107235783Skib 108235783Skib aux_data = device_get_softc(idev); 109235783Skib 110235783Skib if (!aux_data->running) 111280183Sdumbbell return (-EIO); 112235783Skib 113235783Skib ret = iic_dp_aux_transaction(idev, MODE_I2C_WRITE, byte, NULL); 114235783Skib return (ret); 115235783Skib} 116235783Skib 117235783Skib/* 118235783Skib * Read a single byte from the current I2C address, the 119235783Skib * I2C link must be running or this returns -EIO 120235783Skib */ 121235783Skibstatic int 122235783Skibiic_dp_aux_get_byte(device_t idev, u8 *byte_ret) 123235783Skib{ 124235783Skib struct iic_dp_aux_data *aux_data; 125235783Skib int ret; 126235783Skib 127235783Skib aux_data = device_get_softc(idev); 128235783Skib 129235783Skib if (!aux_data->running) 130280183Sdumbbell return (-EIO); 131235783Skib 132235783Skib ret = iic_dp_aux_transaction(idev, MODE_I2C_READ, 0, byte_ret); 133235783Skib return (ret); 134235783Skib} 135235783Skib 136235783Skibstatic int 137235783Skibiic_dp_aux_xfer(device_t idev, struct iic_msg *msgs, uint32_t num) 138235783Skib{ 139235783Skib u8 *buf; 140235783Skib int b, m, ret; 141235783Skib u16 len; 142235783Skib bool reading; 143235783Skib 144235783Skib ret = 0; 145235783Skib reading = false; 146235783Skib 147235783Skib for (m = 0; m < num; m++) { 148235783Skib len = msgs[m].len; 149235783Skib buf = msgs[m].buf; 150235783Skib reading = (msgs[m].flags & IIC_M_RD) != 0; 151249249Sdumbbell ret = iic_dp_aux_address(idev, msgs[m].slave >> 1, reading); 152296548Sdumbbell if (ret < 0) 153235783Skib break; 154235783Skib if (reading) { 155235783Skib for (b = 0; b < len; b++) { 156235783Skib ret = iic_dp_aux_get_byte(idev, &buf[b]); 157235783Skib if (ret != 0) 158235783Skib break; 159235783Skib } 160235783Skib } else { 161235783Skib for (b = 0; b < len; b++) { 162235783Skib ret = iic_dp_aux_put_byte(idev, buf[b]); 163296548Sdumbbell if (ret < 0) 164235783Skib break; 165235783Skib } 166235783Skib } 167235783Skib if (ret != 0) 168235783Skib break; 169235783Skib } 170235783Skib iic_dp_aux_stop(idev, reading); 171235783Skib DRM_DEBUG_KMS("dp_aux_xfer return %d\n", ret); 172280183Sdumbbell return (-ret); 173235783Skib} 174235783Skib 175235783Skibstatic void 176235783Skibiic_dp_aux_reset_bus(device_t idev) 177235783Skib{ 178235783Skib 179235783Skib (void)iic_dp_aux_address(idev, 0, false); 180235783Skib (void)iic_dp_aux_stop(idev, false); 181235783Skib} 182235783Skib 183235783Skibstatic int 184235783Skibiic_dp_aux_reset(device_t idev, u_char speed, u_char addr, u_char *oldaddr) 185235783Skib{ 186235783Skib 187235783Skib iic_dp_aux_reset_bus(idev); 188280183Sdumbbell return (0); 189235783Skib} 190235783Skib 191235783Skibstatic int 192235783Skibiic_dp_aux_prepare_bus(device_t idev) 193235783Skib{ 194235783Skib 195235783Skib /* adapter->retries = 3; */ 196235783Skib iic_dp_aux_reset_bus(idev); 197235783Skib return (0); 198235783Skib} 199235783Skib 200235783Skibstatic int 201235783Skibiic_dp_aux_probe(device_t idev) 202235783Skib{ 203235783Skib 204235783Skib return (BUS_PROBE_DEFAULT); 205235783Skib} 206235783Skib 207235783Skibstatic int 208235783Skibiic_dp_aux_attach(device_t idev) 209235783Skib{ 210235783Skib struct iic_dp_aux_data *aux_data; 211235783Skib 212235783Skib aux_data = device_get_softc(idev); 213235783Skib aux_data->port = device_add_child(idev, "iicbus", -1); 214235783Skib if (aux_data->port == NULL) 215235783Skib return (ENXIO); 216235783Skib device_quiet(aux_data->port); 217235783Skib bus_generic_attach(idev); 218235783Skib return (0); 219235783Skib} 220235783Skib 221235783Skibint 222235783Skibiic_dp_aux_add_bus(device_t dev, const char *name, 223235783Skib int (*ch)(device_t idev, int mode, uint8_t write_byte, uint8_t *read_byte), 224235783Skib void *priv, device_t *bus, device_t *adapter) 225235783Skib{ 226235783Skib device_t ibus; 227235783Skib struct iic_dp_aux_data *data; 228235783Skib int idx, error; 229235783Skib static int dp_bus_counter; 230235783Skib 231235783Skib mtx_lock(&Giant); 232235783Skib 233235783Skib idx = atomic_fetchadd_int(&dp_bus_counter, 1); 234235783Skib ibus = device_add_child(dev, "drm_iic_dp_aux", idx); 235235783Skib if (ibus == NULL) { 236235783Skib mtx_unlock(&Giant); 237235783Skib DRM_ERROR("drm_iic_dp_aux bus %d creation error\n", idx); 238235783Skib return (-ENXIO); 239235783Skib } 240235783Skib device_quiet(ibus); 241235783Skib error = device_probe_and_attach(ibus); 242235783Skib if (error != 0) { 243235783Skib device_delete_child(dev, ibus); 244235783Skib mtx_unlock(&Giant); 245235783Skib DRM_ERROR("drm_iic_dp_aux bus %d attach failed, %d\n", 246235783Skib idx, error); 247235783Skib return (-error); 248235783Skib } 249235783Skib data = device_get_softc(ibus); 250235783Skib data->running = false; 251235783Skib data->address = 0; 252235783Skib data->aux_ch = ch; 253235783Skib data->priv = priv; 254235783Skib error = iic_dp_aux_prepare_bus(ibus); 255235783Skib if (error == 0) { 256235783Skib *bus = ibus; 257235783Skib *adapter = data->port; 258235783Skib } 259235783Skib mtx_unlock(&Giant); 260280183Sdumbbell return (-error); 261235783Skib} 262235783Skib 263235783Skibstatic device_method_t drm_iic_dp_aux_methods[] = { 264235783Skib DEVMETHOD(device_probe, iic_dp_aux_probe), 265235783Skib DEVMETHOD(device_attach, iic_dp_aux_attach), 266254819Sdumbbell DEVMETHOD(device_detach, bus_generic_detach), 267235783Skib DEVMETHOD(iicbus_reset, iic_dp_aux_reset), 268235783Skib DEVMETHOD(iicbus_transfer, iic_dp_aux_xfer), 269235783Skib DEVMETHOD_END 270235783Skib}; 271235783Skibstatic driver_t drm_iic_dp_aux_driver = { 272235783Skib "drm_iic_dp_aux", 273235783Skib drm_iic_dp_aux_methods, 274235783Skib sizeof(struct iic_dp_aux_data) 275235783Skib}; 276235783Skibstatic devclass_t drm_iic_dp_aux_devclass; 277235783SkibDRIVER_MODULE_ORDERED(drm_iic_dp_aux, drmn, drm_iic_dp_aux_driver, 278235783Skib drm_iic_dp_aux_devclass, 0, 0, SI_ORDER_SECOND); 279