/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License (the "License"). * You may not use this file except in compliance with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright 2008 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ /* * This is the nexus driver for SMBUS devices. It mostly does not use * the SMBUS protocol so that it fits better into the solaris i2c * framework. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * static function declarations */ static uint_t smbus_intr_cmn(smbus_t *smbus, char *src); static void smbus_intr_timeout(void *arg); static void smbus_resume(dev_info_t *dip); static void smbus_suspend(dev_info_t *dip); static int smbus_bus_ctl(dev_info_t *dip, dev_info_t *rdip, ddi_ctl_enum_t op, void *arg, void *result); static int smbus_acquire(smbus_t *, dev_info_t *dip, i2c_transfer_t *tp); static void smbus_release(smbus_t *); static int smbus_attach(dev_info_t *dip, ddi_attach_cmd_t cmd); static int smbus_detach(dev_info_t *dip, ddi_detach_cmd_t cmd); static void smbus_free_regs(smbus_t *smbus); static int smbus_setup_regs(dev_info_t *dip, smbus_t *smbus); static void smbus_reportdev(dev_info_t *dip, dev_info_t *rdip); static void smbus_uninitchild(dev_info_t *cdip); static int smbus_initchild(dev_info_t *cdip); static int smbus_rd(smbus_t *smbus); static int smbus_wr(smbus_t *smbus); static void smbus_put(smbus_t *smbus, uint8_t reg, uint8_t data, uint8_t flags); static uint8_t smbus_get(smbus_t *smbus, uint8_t reg); static int smbus_dip_to_addr(dev_info_t *dip); static uint_t smbus_intr(caddr_t arg); static int smbus_switch(smbus_t *smbus); static struct bus_ops smbus_busops = { BUSO_REV, nullbusmap, /* bus_map */ NULL, /* bus_get_intrspec */ NULL, /* bus_add_intrspec */ NULL, /* bus_remove_intrspec */ NULL, /* bus_map_fault */ ddi_no_dma_map, /* bus_dma_map */ ddi_no_dma_allochdl, /* bus_dma_allochdl */ ddi_no_dma_freehdl, /* bus_dma_freehdl */ ddi_no_dma_bindhdl, /* bus_dma_bindhdl */ ddi_no_dma_unbindhdl, /* bus_unbindhdl */ ddi_no_dma_flush, /* bus_dma_flush */ ddi_no_dma_win, /* bus_dma_win */ ddi_no_dma_mctl, /* bus_dma_ctl */ smbus_bus_ctl, /* bus_ctl */ ddi_bus_prop_op, /* bus_prop_op */ NULL, /* bus_get_eventcookie */ NULL, /* bus_add_eventcall */ NULL, /* bus_remove_eventcall */ NULL, /* bus_post_event */ 0, /* bus_intr_ctl */ 0, /* bus_config */ 0, /* bus_unconfig */ 0, /* bus_fm_init */ 0, /* bus_fm_fini */ 0, /* bus_fm_access_enter */ 0, /* bus_fm_access_exit */ 0, /* bus_power */ i_ddi_intr_ops /* bus_intr_op */ }; struct cb_ops smbus_cb_ops = { nodev, /* open */ nodev, /* close */ nodev, /* strategy */ nodev, /* print */ nodev, /* dump */ nodev, /* read */ nodev, /* write */ nodev, /* ioctl */ nodev, /* devmap */ nodev, /* mmap */ nodev, /* segmap */ nochpoll, /* poll */ ddi_prop_op, /* cb_prop_op */ 0, /* streamtab */ D_MP | D_NEW /* Driver compatibility flag */ }; static struct dev_ops smbus_ops = { DEVO_REV, 0, ddi_no_info, nulldev, nulldev, smbus_attach, smbus_detach, nodev, &smbus_cb_ops, &smbus_busops, NULL, ddi_quiesce_not_supported, /* devo_quiesce */ }; static struct modldrv modldrv = { &mod_driverops, /* Type of module. This one is a driver */ "SMBUS nexus Driver", /* Name of the module. */ &smbus_ops, /* driver ops */ }; static struct modlinkage modlinkage = { MODREV_1, &modldrv, NULL }; /* * Globals */ static void *smbus_state; static int intr_timeout = INTR_TIMEOUT; /* * The "interrupt-priorities" property is how a driver can specify a SPARC * PIL level to associate with each of its interrupt properties. Most * self-identifying busses have a better mechanism for managing this, but I2C * doesn't. */ int smbus_pil = SMBUS_PIL; i2c_nexus_reg_t smbus_regvec = { I2C_NEXUS_REV, smbus_transfer, }; #ifdef DEBUG static int smbus_print_lvl = 0; static char msg_buff[1024]; static kmutex_t msg_buf_lock; void smbus_print(int flags, const char *fmt, ...) { if (flags & smbus_print_lvl) { va_list ap; va_start(ap, fmt); if (smbus_print_lvl & PRT_PROM) { prom_vprintf(fmt, ap); } else { mutex_enter(&msg_buf_lock); (void) vsprintf(msg_buff, fmt, ap); if (smbus_print_lvl & PRT_BUFFONLY) { cmn_err(CE_CONT, "?%s", msg_buff); } else { cmn_err(CE_CONT, "%s", msg_buff); } mutex_exit(&msg_buf_lock); } va_end(ap); } } #endif /* DEBUG */ int _init(void) { int status; status = ddi_soft_state_init(&smbus_state, sizeof (smbus_t), 1); if (status != 0) { return (status); } if ((status = mod_install(&modlinkage)) != 0) { ddi_soft_state_fini(&smbus_state); } else { #ifdef DEBUG mutex_init(&msg_buf_lock, NULL, MUTEX_DRIVER, NULL); #endif } return (status); } int _fini(void) { int status; if ((status = mod_remove(&modlinkage)) == 0) { ddi_soft_state_fini(&smbus_state); #ifdef DEBUG mutex_destroy(&msg_buf_lock); #endif } return (status); } /* * The loadable-module _info(9E) entry point */ int _info(struct modinfo *modinfop) { return (mod_info(&modlinkage, modinfop)); } static void smbus_interrupts_on(smbus_t *smbus) { int src_enable; src_enable = ddi_get32(smbus->smbus_confighandle, (uint32_t *)&smbus->smbus_configregaddr[SMBUS_SRC_ENA]); src_enable |= SMBUS_SMI; ddi_put32(smbus->smbus_confighandle, (uint32_t *)&smbus->smbus_configregaddr[SMBUS_SRC_ENA], src_enable); (void) ddi_get32(smbus->smbus_confighandle, (uint32_t *)&smbus->smbus_configregaddr[SMBUS_SRC_ENA]); } static void smbus_interrupts_off(smbus_t *smbus) { int src_enable; src_enable = ddi_get32(smbus->smbus_confighandle, (uint32_t *)&smbus->smbus_configregaddr[SMBUS_SRC_ENA]); src_enable &= ~SMBUS_SMI; ddi_put32(smbus->smbus_confighandle, (uint32_t *)&smbus->smbus_configregaddr[SMBUS_SRC_ENA], src_enable); (void) ddi_get32(smbus->smbus_confighandle, (uint32_t *)&smbus->smbus_configregaddr[SMBUS_SRC_ENA]); } static void smbus_dodetach(dev_info_t *dip) { smbus_t *smbus; int instance = ddi_get_instance(dip); smbus = ddi_get_soft_state(smbus_state, instance); if (smbus == NULL) { return; } cv_destroy(&smbus->smbus_cv); mutex_destroy(&smbus->smbus_mutex); if ((smbus->smbus_attachflags & INTERRUPT_PRI) != 0) { (void) ddi_prop_remove(DDI_DEV_T_NONE, dip, "interrupt-priorities"); } smbus_free_regs(smbus); if ((smbus->smbus_attachflags & NEXUS_REGISTER) != 0) { i2c_nexus_unregister(dip); } if ((smbus->smbus_attachflags & IMUTEX) != 0) { mutex_destroy(&smbus->smbus_imutex); cv_destroy(&smbus->smbus_icv); } if (smbus->smbus_timeout != 0) { (void) untimeout(smbus->smbus_timeout); } if ((smbus->smbus_attachflags & ADD_INTR) != 0) { ddi_remove_intr(dip, 0, smbus->smbus_icookie); } ddi_soft_state_free(smbus_state, instance); } static int smbus_doattach(dev_info_t *dip) { smbus_t *smbus; int instance = ddi_get_instance(dip); /* * Allocate soft state structure. */ if (ddi_soft_state_zalloc(smbus_state, instance) != DDI_SUCCESS) { goto bad; } smbus = ddi_get_soft_state(smbus_state, instance); (void) snprintf(smbus->smbus_name, sizeof (smbus->smbus_name), "%s%d", ddi_node_name(dip), instance); smbus->smbus_dip = dip; mutex_init(&smbus->smbus_mutex, NULL, MUTEX_DRIVER, NULL); mutex_init(&smbus->smbus_imutex, NULL, MUTEX_DRIVER, NULL); cv_init(&smbus->smbus_cv, NULL, CV_DRIVER, NULL); cv_init(&smbus->smbus_intr_cv, NULL, CV_DRIVER, NULL); if (smbus_setup_regs(dip, smbus) != DDI_SUCCESS) { goto bad; } if (ddi_prop_exists(DDI_DEV_T_ANY, dip, DDI_PROP_DONTPASS, "interrupts") == 1) { smbus->smbus_polling = 0; /* * The "interrupt-priorities" property is how a driver can * specify a SPARC PIL level to associate with each of its * interrupt properties. Most self-identifying busses have * a better mechanism for managing this, but I2C doesn't. */ if (ddi_prop_exists(DDI_DEV_T_ANY, dip, DDI_PROP_NOTPROM | DDI_PROP_DONTPASS, "interrupt-priorities") != 1) { (void) ddi_prop_create(DDI_DEV_T_NONE, dip, DDI_PROP_CANSLEEP, "interrupt-priorities", (caddr_t)&smbus_pil, sizeof (smbus_pil)); smbus->smbus_attachflags |= INTERRUPT_PRI; } /* * Clear status to clear any possible interrupt */ smbus_put(smbus, SMB_STS, 0xff, SMBUS_FLUSH); if (ddi_get_iblock_cookie(dip, 0, &smbus->smbus_icookie) != DDI_SUCCESS) { goto bad; } if (ddi_add_intr(dip, 0, NULL, NULL, smbus_intr, (caddr_t)smbus) != DDI_SUCCESS) { cmn_err(CE_WARN, "%s failed to add interrupt", smbus->smbus_name); goto bad; } smbus->smbus_attachflags |= ADD_INTR; } else { smbus->smbus_polling = 1; /* Clear status */ smbus_put(smbus, SMB_STS, 0xff, SMBUS_FLUSH); } /* * initialize a cv and mutex */ cv_init(&smbus->smbus_icv, NULL, CV_DRIVER, NULL); mutex_init(&smbus->smbus_imutex, NULL, MUTEX_DRIVER, (void *)smbus->smbus_icookie); smbus->smbus_attachflags |= IMUTEX; /* * Register with the i2c framework */ i2c_nexus_register(dip, &smbus_regvec); smbus->smbus_attachflags |= NEXUS_REGISTER; return (DDI_SUCCESS); bad: smbus_dodetach(dip); return (DDI_FAILURE); } static int smbus_attach(dev_info_t *dip, ddi_attach_cmd_t cmd) { switch (cmd) { case DDI_ATTACH: return (smbus_doattach(dip)); case DDI_RESUME: smbus_resume(dip); return (DDI_SUCCESS); default: return (DDI_FAILURE); } } static int smbus_detach(dev_info_t *dip, ddi_detach_cmd_t cmd) { switch (cmd) { case DDI_DETACH: smbus_dodetach(dip); return (DDI_SUCCESS); case DDI_SUSPEND: smbus_suspend(dip); return (DDI_SUCCESS); default: return (DDI_FAILURE); } } static int smbus_bus_ctl(dev_info_t *dip, dev_info_t *rdip, ddi_ctl_enum_t op, void *arg, void *result) { switch (op) { case DDI_CTLOPS_INITCHILD: return (smbus_initchild((dev_info_t *)arg)); case DDI_CTLOPS_UNINITCHILD: smbus_uninitchild((dev_info_t *)arg); return (DDI_SUCCESS); case DDI_CTLOPS_REPORTDEV: smbus_reportdev(dip, rdip); return (DDI_SUCCESS); case DDI_CTLOPS_DMAPMAPC: case DDI_CTLOPS_POKE: case DDI_CTLOPS_PEEK: case DDI_CTLOPS_IOMIN: case DDI_CTLOPS_REPORTINT: case DDI_CTLOPS_SIDDEV: case DDI_CTLOPS_SLAVEONLY: case DDI_CTLOPS_AFFINITY: case DDI_CTLOPS_PTOB: case DDI_CTLOPS_BTOP: case DDI_CTLOPS_BTOPR: case DDI_CTLOPS_DVMAPAGESIZE: return (DDI_FAILURE); default: return (ddi_ctlops(dip, rdip, op, arg, result)); } } static int smbus_initchild(dev_info_t *cdip) { int32_t cell_size; int len; int32_t regs[2]; int err; smbus_ppvt_t *ppvt; char name[30]; SMBUS_PRINT((PRT_INIT, "smbus_initchild ENTER: %s\n", ddi_node_name(cdip))); len = sizeof (cell_size); err = ddi_getlongprop_buf(DDI_DEV_T_ANY, cdip, DDI_PROP_CANSLEEP, "#address-cells", (caddr_t)&cell_size, &len); if (err != DDI_PROP_SUCCESS || len != sizeof (cell_size)) { cmn_err(CE_WARN, "cannot find address-cells"); return (DDI_FAILURE); } len = sizeof (regs); err = ddi_getlongprop_buf(DDI_DEV_T_ANY, cdip, DDI_PROP_DONTPASS | DDI_PROP_CANSLEEP, "reg", (caddr_t)regs, &len); if (err != DDI_PROP_SUCCESS) { cmn_err(CE_WARN, "cannot get reg property"); return (DDI_FAILURE); } ppvt = kmem_zalloc(sizeof (smbus_ppvt_t), KM_SLEEP); ddi_set_parent_data(cdip, ppvt); /* * The reg property contains an unused first element (which is * the mux addr on xcal), and the second element is the i2c bus * address of the device. */ ppvt->smbus_ppvt_addr = regs[1]; (void) sprintf(name, "%x", regs[1]); ddi_set_name_addr(cdip, name); SMBUS_PRINT((PRT_INIT, "smbus_initchild SUCCESS: %s\n", ddi_node_name(cdip))); return (DDI_SUCCESS); } static void smbus_uninitchild(dev_info_t *cdip) { smbus_ppvt_t *ppvt; ppvt = ddi_get_parent_data(cdip); ddi_set_parent_data(cdip, NULL); ddi_set_name_addr(cdip, NULL); kmem_free(ppvt, sizeof (smbus_ppvt_t)); SMBUS_PRINT((PRT_INIT, "smbus_uninitchild: %s\n", ddi_node_name(cdip))); } static void smbus_reportdev(dev_info_t *dip, dev_info_t *rdip) { smbus_ppvt_t *ppvt; ppvt = ddi_get_parent_data(rdip); cmn_err(CE_CONT, "?%s%d at %s%d: addr 0x%x", ddi_driver_name(rdip), ddi_get_instance(rdip), ddi_driver_name(dip), ddi_get_instance(dip), ppvt->smbus_ppvt_addr); } /* * smbus_setup_regs() is called to map in the registers * specific to the smbus. */ static int smbus_setup_regs(dev_info_t *dip, smbus_t *smbus) { ddi_device_acc_attr_t attr; int ret; attr.devacc_attr_version = DDI_DEVICE_ATTR_V0; attr.devacc_attr_endian_flags = DDI_STRUCTURE_LE_ACC; attr.devacc_attr_dataorder = DDI_STRICTORDER_ACC; ret = ddi_regs_map_setup(dip, 1, (caddr_t *)&smbus->smbus_regaddr, 0, 0, &attr, &smbus->smbus_rhandle); if (ret == DDI_FAILURE) { cmn_err(CE_WARN, "%s unable to map regs", smbus->smbus_name); } else if (ret == DDI_REGS_ACC_CONFLICT) { cmn_err(CE_WARN, "%s unable to map regs because of conflict", smbus->smbus_name); ret = DDI_FAILURE; } if (ret == DDI_FAILURE) { return (ret); } ret = ddi_regs_map_setup(dip, 0, (caddr_t *)&smbus->smbus_configregaddr, 0, 0, &attr, &smbus->smbus_confighandle); if (ret == DDI_FAILURE) { cmn_err(CE_WARN, "%s unable to map config regs", smbus->smbus_name); } else if (ret == DDI_REGS_ACC_CONFLICT) { cmn_err(CE_WARN, "%s unable to map config regs because of conflict", smbus->smbus_name); ret = DDI_FAILURE; } return (ret); } /* * smbus_free_regs() frees any registers previously allocated. */ static void smbus_free_regs(smbus_t *smbus) { if (smbus->smbus_regaddr != NULL) { ddi_regs_map_free(&smbus->smbus_rhandle); } if (smbus->smbus_configregaddr != NULL) { ddi_regs_map_free(&smbus->smbus_confighandle); } } /* * smbus_dip_to_addr() takes a dip and returns an I2C address. */ static int smbus_dip_to_addr(dev_info_t *cdip) { smbus_ppvt_t *ppvt; ppvt = ddi_get_parent_data(cdip); return (ppvt->smbus_ppvt_addr); } /* * smbus_suspend() is called before the system suspends. Existing * transfer in progress or waiting will complete, but new transfers are * effectively blocked by "acquiring" the bus. */ static void smbus_suspend(dev_info_t *dip) { smbus_t *smbus; int instance; instance = ddi_get_instance(dip); smbus = ddi_get_soft_state(smbus_state, instance); (void) smbus_acquire(smbus, NULL, NULL); } /* * smbus_resume() is called when the system resumes from CPR. It releases * the hold that was placed on the i2c bus, which allows any real * transfers to continue. */ static void smbus_resume(dev_info_t *dip) { smbus_t *smbus; int instance; instance = ddi_get_instance(dip); smbus = ddi_get_soft_state(smbus_state, instance); smbus_release(smbus); } /* * smbus_acquire() is called by a thread wishing to "own" the SMbus. * It should not be held across multiple transfers. */ static int smbus_acquire(smbus_t *smbus, dev_info_t *dip, i2c_transfer_t *tp) { mutex_enter(&smbus->smbus_mutex); while (smbus->smbus_busy) { cv_wait(&smbus->smbus_cv, &smbus->smbus_mutex); } smbus->smbus_busy = 1; mutex_exit(&smbus->smbus_mutex); /* * On systems where OBP shares a smbus controller with the * OS, plat_shared_i2c_enter will serialize access to the * smbus controller. Do not grab this lock during CPR * suspend as the CPR thread also acquires this muxex * through through prom_setprop which causes recursive * mutex enter. * * dip == NULL during CPR. */ if ((&plat_shared_i2c_enter != NULL) && (dip != NULL)) { plat_shared_i2c_enter(smbus->smbus_dip); } smbus->smbus_cur_tran = tp; smbus->smbus_cur_dip = dip; return (SMBUS_SUCCESS); } /* * smbus_release() is called to release a hold made by smbus_acquire(). */ static void smbus_release(smbus_t *smbus) { mutex_enter(&smbus->smbus_mutex); smbus->smbus_busy = 0; cv_signal(&smbus->smbus_cv); smbus->smbus_cur_tran = NULL; smbus->smbus_cur_dip = NULL; mutex_exit(&smbus->smbus_mutex); if ((&plat_shared_i2c_exit != NULL) && (smbus->smbus_cur_dip != NULL)) { plat_shared_i2c_exit(smbus->smbus_dip); } } static void smbus_put(smbus_t *smbus, uint8_t reg, uint8_t data, uint8_t flags) { ddi_acc_handle_t hp = smbus->smbus_rhandle; uint8_t *reg_addr = smbus->smbus_regaddr; uint8_t *config_addr = smbus->smbus_configregaddr; ddi_acc_handle_t config_handle = smbus->smbus_confighandle; ddi_put8(hp, ®_addr[reg], data); SMBUS_PRINT((PRT_PUT, "smbus_put: addr = %p data = %x\n", ®_addr[reg], data)); /* * if FLUSH flag is passed, read a config regs to make sure * data written is flushed. */ if (flags & SMBUS_FLUSH) { (void) ddi_get8(config_handle, &config_addr[0]); } } static uint8_t smbus_get(smbus_t *smbus, uint8_t reg) { ddi_acc_handle_t hp = smbus->smbus_rhandle; uint8_t *regaddr = smbus->smbus_regaddr; uint8_t data; data = ddi_get8(hp, ®addr[reg]); SMBUS_PRINT((PRT_GET, "smbus_get: data = %x\n", data)); return (data); } /* * The southbridge smbus device appears to have a feature where * reads from the status register return 0 for a few microseconds * after clearing the status. * * "status_wait_idle" allows for this by retrying until * it gets the right answer or times out. The loop count * and the delay are empirical. The routine uses up * 400 us if it fails. * * The fact that this routine waits for 10 us before the * first check is deliberate. */ static int smbus_wait_idle(smbus_t *smbus) { int retries = 40; int status; smbus_put(smbus, SMB_STS, 0xff, SMBUS_FLUSH); do { drv_usecwait(10); status = smbus_get(smbus, SMB_STS); } while (status != IDLE && --retries > 0); return (status); } /* * smbus_transfer is the function that is registered with * I2C services to be called for each i2c transaction. */ int smbus_transfer(dev_info_t *dip, i2c_transfer_t *tp) { smbus_t *smbus; uint8_t status; clock_t ctime; smbus = ddi_get_soft_state(smbus_state, ddi_get_instance(ddi_get_parent(dip))); if (smbus_acquire(smbus, dip, tp) == SMBUS_FAILURE) { tp->i2c_result = I2C_FAILURE; return (I2C_FAILURE); } tp->i2c_r_resid = tp->i2c_rlen; tp->i2c_w_resid = tp->i2c_wlen; tp->i2c_result = I2C_SUCCESS; smbus->smbus_retries = 0; smbus->smbus_bytes_to_read = 0; mutex_enter(&smbus->smbus_imutex); SMBUS_PRINT((PRT_TRANS, "smbus_transfer: rlen=%d wlen=%d flags=%d", tp->i2c_r_resid, tp->i2c_w_resid, tp->i2c_flags)); /* * First clear the status bits, then read them back to determine * the current state. */ status = smbus_wait_idle(smbus); if (status != IDLE) { /* * Try to issue bus reset * First reset the state machine. */ smbus_put(smbus, SMB_TYP, KILL, SMBUS_FLUSH); status = smbus_wait_idle(smbus); if (status != IDLE) { smbus_put(smbus, SMB_TYP, T_OUT, SMBUS_FLUSH); status = smbus_wait_idle(smbus); if (status != IDLE) { cmn_err(CE_WARN, "%s smbus not idle. Unable to reset %x", smbus->smbus_name, status); smbus->smbus_cur_tran->i2c_result = I2C_FAILURE; mutex_exit(&smbus->smbus_imutex); smbus_release(smbus); return (I2C_FAILURE); } else { cmn_err(CE_WARN, "%s T_OUT reset required", smbus->smbus_name); } } } if (smbus_switch(smbus) != SMBUS_COMPLETE) { if (smbus->smbus_polling) { smbus->smbus_poll_complete = 0; smbus->smbus_poll_retries = 0; do { drv_usecwait(SMBUS_POLL_INTERVAL); (void) smbus_intr_cmn(smbus, SMBUS_POLL); } while (!smbus->smbus_poll_complete); } else { /* * Start a timeout as there is a bug in southbridge * smbus where sometimes a transaction never starts, * and needs to be reinitiated. */ smbus->smbus_timeout = timeout(smbus_intr_timeout, smbus, drv_usectohz(intr_timeout)); SMBUS_PRINT((PRT_TRANS, "starting timeout in smbus_transfer %p", smbus->smbus_timeout)); ctime = ddi_get_lbolt(); ctime += drv_usectohz(SMBUS_TRANS_TIMEOUT); smbus_interrupts_on(smbus); cv_wait(&smbus->smbus_icv, &smbus->smbus_imutex); } } mutex_exit(&smbus->smbus_imutex); smbus_release(smbus); return (tp->i2c_result); } /* * This is called by smbus_intr_cmn() to figure out whether to call * smbus_wr or smbus_rd depending on the command and current state. */ static int smbus_switch(smbus_t *smbus) { int ret; i2c_transfer_t *tp = smbus->smbus_cur_tran; if (tp == NULL) { cmn_err(CE_WARN, "%s smbus_cur_tran is NULL. Transaction failed", smbus->smbus_name); return (SMBUS_FAILURE); } smbus->smbus_saved_w_resid = tp->i2c_w_resid; switch (tp->i2c_flags) { case I2C_WR: ret = smbus_wr(smbus); break; case I2C_RD: ret = smbus_rd(smbus); break; case I2C_WR_RD: /* * We could do a bit more decoding here, * to allow the transactions that would * work as a single smbus command to * be done as such. It's not really * worth the trouble. */ if (tp->i2c_w_resid > 0) { ret = smbus_wr(smbus); } else { ret = smbus_rd(smbus); } break; default: tp->i2c_result = I2C_FAILURE; ret = SMBUS_COMPLETE; break; } return (ret); } /* * */ static void smbus_intr_timeout(void *arg) { smbus_t *smbus = (smbus_t *)arg; mutex_enter(&smbus->smbus_imutex); /* * If timeout is already cleared, it means interrupt arrived * while timeout fired. In this case, just return from here. */ if (smbus->smbus_timeout == 0) { mutex_exit(&smbus->smbus_imutex); return; } (void) smbus_intr_cmn(smbus, SMBUS_TIMEOUT); mutex_exit(&smbus->smbus_imutex); } /* * smbus_intr() is the interrupt handler for smbus. */ static uint_t smbus_intr(caddr_t arg) { smbus_t *smbus = (smbus_t *)arg; uint32_t intr_status; uint_t result; /* * Check to see if intr is really from smbus */ intr_status = ddi_get32(smbus->smbus_confighandle, (uint32_t *)&smbus->smbus_configregaddr[SMBUS_SRC_STATUS]); if ((intr_status & SMBUS_SMB_INTR_STATUS) == 0) { SMBUS_PRINT((PRT_INTR, "smbus_intr: intr not from smbus\n")); return (DDI_INTR_UNCLAIMED); } mutex_enter(&smbus->smbus_imutex); /* * If timeout is already cleared, it means it arrived before the intr. * In that case, just return from here. */ if (smbus->smbus_timeout == 0) { mutex_exit(&smbus->smbus_imutex); return (DDI_INTR_CLAIMED); } result = smbus_intr_cmn(smbus, SMBUS_INTR); mutex_exit(&smbus->smbus_imutex); return (result); } /* * smbus_intr() is the interrupt handler for smbus. */ static uint_t smbus_intr_cmn(smbus_t *smbus, char *src) { i2c_transfer_t *tp; char error_str[128]; uint8_t status; int ret = SMBUS_SUCCESS; timeout_id_t timer_id; ASSERT(mutex_owned(&smbus->smbus_imutex)); error_str[0] = '\0'; smbus_interrupts_off(smbus); tp = smbus->smbus_cur_tran; /* * This only happens when top half is interrupted or * times out, then the interrupt arrives. Interrupt * was already disabled by top half, so just exit. */ if (tp == NULL) { return (DDI_INTR_CLAIMED); } /* * This wait is required before reading the status, otherwise * a parity error can occur which causes a panic. A bug with * southbridge SMBUS. */ drv_usecwait(15); status = smbus_get(smbus, SMB_STS); if (smbus->smbus_polling) { /* * If we are polling, then we expect not to * get the right answer for a while, * so we don't go on to that error stuff * until we've polled the status for a * few times. We check for errors here to save time, * otherwise we would have to wait for the full * poll timeout before dealing with them. */ if (status != (CMD_CMPL|IDLE) && (status & (FAILED|BUS_ERR|DRV_ERR)) == 0 && smbus->smbus_poll_retries++ < SMBUS_POLL_MAX_RETRIES) { return (DDI_INTR_CLAIMED); } /* * else either ... * [] the command has completed, or; * [] There has been an error, or; * [] we timed out waiting for something useful * to happen, so we go on to to the error handling bit that * follows, * which will reset the controller then restart the * whole transaction. * * In all cases, clear "poll_retries" for the next command or * retry */ smbus->smbus_poll_retries = 0; } /* * A bug in southbridge SMBUS sometimes requires a reset. Status * should NOT be IDLE without any other bit set. If it is, the * transaction should be restarted. */ if (status == IDLE) { (void) sprintf(error_str, "%s bus is idle, ", error_str); } if ((status & CMD_CMPL) == 0) { (void) sprintf(error_str, "%s command failed to complete, ", error_str); } if (status & BUS_ERR) { (void) sprintf(error_str, "%s bus error, ", error_str); } if (status & FAILED) { (void) sprintf(error_str, "%s failed transaction, ", error_str); } if (status & DRV_ERR) { (void) sprintf(error_str, "%s timeout or bus reset", error_str); } if (error_str[0] != '\0') { (void) sprintf(error_str, "%s %s ", error_str, src); } /* * Clear status to clear the interrupt. */ smbus_put(smbus, SMB_STS, 0xff, SMBUS_FLUSH); if (error_str[0] != '\0') { smbus_put(smbus, SMB_TYP, KILL, SMBUS_FLUSH); if (smbus->smbus_retries++ < SMBUS_MAX_RETRIES) { /* * XXXX There was a panic here when the * intr timeout was greater than the timeout * for the entire transfer. * * Restore the value of w_resid before the * last transaction. r_resid doesn't need to * be restored because it is only decremented * after a successful read. Need to do this * here since smbus_switch() keys off of a * resid to know whether to call smbus_rd() or * smbus_wr(). */ tp->i2c_w_resid = smbus->smbus_saved_w_resid; smbus->smbus_bytes_to_read = 0; SMBUS_PRINT((PRT_INTR_ERR, "retrying: %s %s w_resid=%d\n", error_str, src, tp->i2c_w_resid)); } else { cmn_err(CE_WARN, "%s max retries exceeded: %s", smbus->smbus_name, error_str); /* * bailing, but first will reset the bus. */ smbus_put(smbus, SMB_TYP, KILL, SMBUS_FLUSH); smbus_put(smbus, SMB_STS, 0xff, SMBUS_FLUSH); smbus->smbus_cur_tran->i2c_result = I2C_FAILURE; ret = SMBUS_FAILURE; } } else { smbus->smbus_retries = 0; } if (tp != NULL) { SMBUS_PRINT((PRT_INTR, "flags=%d wresid=%d r_resid=%d %s\n", tp->i2c_flags, tp->i2c_w_resid, tp->i2c_r_resid, src)); } if (ret != SMBUS_FAILURE) { ret = smbus_switch(smbus); } if (smbus->smbus_polling) { if (ret == SMBUS_COMPLETE || ret == SMBUS_FAILURE) { smbus->smbus_poll_complete = 1; } } else { /* * Disable previous timeout. In case it was about to fire this * will let it exit without doing anything. */ timer_id = smbus->smbus_timeout; smbus->smbus_timeout = 0; mutex_exit(&smbus->smbus_imutex); (void) untimeout(timer_id); mutex_enter(&smbus->smbus_imutex); if (ret == SMBUS_COMPLETE || ret == SMBUS_FAILURE) { cv_signal(&smbus->smbus_icv); } else { smbus_interrupts_on(smbus); smbus->smbus_timeout = timeout(smbus_intr_timeout, smbus, drv_usectohz(intr_timeout)); SMBUS_PRINT((PRT_INTR, "smbus_intr starting timeout %p " "%s", smbus->smbus_timeout, src)); } } return (DDI_INTR_CLAIMED); } /* * smbus_wr handles writes to the smbus. Unlike true I2C busses * such as provided by pcf8584, smbus attaches a start and stop bit for each * transaction, so this limits writes to the maximum number of bytes * in a single transaction, which is 33. * * If more than 33 bytes are contained in the transfer, a non-zero * residual has to be returned, and the calling driver has to restart * another transaction to complete writing out any remaining data. The * reason for this is that most devices require a register/offset as the * first byte to be written for each SMBUS transaction. */ static int smbus_wr(smbus_t *smbus) { i2c_transfer_t *tp = smbus->smbus_cur_tran; uint8_t addr = smbus_dip_to_addr(smbus->smbus_cur_dip); int bytes_written = 0; uint8_t a; uint8_t b; if (tp->i2c_w_resid != tp->i2c_wlen) { return (SMBUS_COMPLETE); } SMBUS_PRINT((PRT_WR, "smbus_wr: addr = %x resid = %d\n", addr, tp->i2c_w_resid)); smbus_put(smbus, SMB_STS, 0xff, 0); /* * Address must be re-written for each command and it has to * be written before SMB_TYP. */ smbus_put(smbus, DEV_ADDR, addr, 0); switch (tp->i2c_w_resid) { case 1: a = tp->i2c_wbuf[tp->i2c_wlen - tp->i2c_w_resid--]; smbus_put(smbus, SMB_CMD, a, 0); smbus_put(smbus, SMB_TYP, SEND_BYTE, 0); SMBUS_PRINT((PRT_WR, "smbus_wr: send one byte:" " %d\n", a)); break; case 2: a = tp->i2c_wbuf[tp->i2c_wlen - tp->i2c_w_resid--]; smbus_put(smbus, SMB_CMD, a, 0); b = tp->i2c_wbuf[tp->i2c_wlen - tp->i2c_w_resid--]; smbus_put(smbus, DEV_DATA0, b, 0); smbus_put(smbus, SMB_TYP, WR_BYTE, 0); SMBUS_PRINT((PRT_WR, "smbus_wr: send two bytes:" " %d %d\n", a, b)); break; default: /* * Write out as many bytes as possible in a single command. * Note that BLK_DATA just creats a byte stream. ie, the * smbus protocol is not used or interpreted by this driver. */ smbus_put(smbus, SMB_TYP, WR_BLK, 0); a = tp->i2c_wbuf[tp->i2c_wlen - tp->i2c_w_resid--]; smbus_put(smbus, SMB_CMD, a, 0); SMBUS_PRINT((PRT_WR, "smbus_wr: send multiple bytes: ")); SMBUS_PRINT((PRT_WR, "%x ", a)); while (tp->i2c_w_resid != 0) { a = tp->i2c_wbuf[tp->i2c_wlen - tp->i2c_w_resid--]; smbus_put(smbus, BLK_DATA, a, 0); SMBUS_PRINT((PRT_WR, "%x ", a)); /* * Note that MAX_BLK_SEND defines how many bytes may * be sent to the BLK_DATA register. The leading byte * already sent to the SMB_CMD register doesn't count * But ALL the BLK_DATA bytes count so pre-increment * bytes_written before testing. */ if (++bytes_written == MAX_BLK_SEND) { break; } } SMBUS_PRINT((PRT_WR, "\n")); smbus_put(smbus, DEV_DATA0, bytes_written, 0); break; } /* * writing anything to port reg starts transfer */ smbus_put(smbus, STR_PORT, 0, SMBUS_FLUSH); return (SMBUS_PENDING); } /* * smbus_rd handles reads to the smbus. Unlike a true I2C bus * such as provided by pcf8584, smbus attaches a start and stop bit * for each transaction, which limits reads to the maximum number of * bytes in a single SMBUS transaction. (Block reads don't * seem to work on smbus, and the southbridge documentation is poor). * * It doesn't appear that reads spanning multiple I2C transactions * (ie each with a start-stop) affects the transfer when reading * multiple bytes from devices with internal counters. The counter * is correctly maintained. * * RD_WORD and RD_BYTE write out the byte in the SMB_CMD register * before reading, so RCV_BYTE is used instead. * * Multi-byte reads iniatiate a SMBUS transaction for each byte to be * received. Because register/offset information doesn't need to * be resent for each I2C transaction (as opposed to when writing data), * the driver can continue reading data in separate SMBUS transactions * until the requested buffer is filled. */ static int smbus_rd(smbus_t *smbus) { i2c_transfer_t *tp = smbus->smbus_cur_tran; uint8_t addr = smbus_dip_to_addr(smbus->smbus_cur_dip); if (smbus->smbus_bytes_to_read == 1) { tp->i2c_rbuf[tp->i2c_rlen - tp->i2c_r_resid] = smbus_get(smbus, DEV_DATA0); SMBUS_PRINT((PRT_RD, "smbus_rd: data in = %d\n", tp->i2c_rbuf[tp->i2c_rlen - tp->i2c_r_resid])); tp->i2c_r_resid--; smbus->smbus_bytes_to_read = 0; if (tp->i2c_r_resid == 0) { return (SMBUS_COMPLETE); } } /* * Address must be re-written for each command. It must * be written before SMB_TYP. */ smbus_put(smbus, DEV_ADDR, addr | I2C_READ, 0); if (tp->i2c_r_resid == 0) { smbus->smbus_bytes_to_read = 0; return (SMBUS_COMPLETE); } smbus->smbus_bytes_to_read = 1; smbus_put(smbus, SMB_TYP, RCV_BYTE, 0); smbus_put(smbus, SMB_STS, 0xff, 0); SMBUS_PRINT((PRT_RD, "smbus_rd: starting a read addr = %x resid = %d " "bytes_to_read=%d\n", addr, tp->i2c_r_resid, smbus->smbus_bytes_to_read)); smbus_put(smbus, STR_PORT, 0, SMBUS_FLUSH); return (SMBUS_PENDING); }