From 011586e8add052f42fb85aa191f7de614cbb6250 Mon Sep 17 00:00:00 2001 From: ian Date: Tue, 20 Oct 2015 21:20:34 +0000 Subject: MFC r281828, r289083, r289084, r289091, r289093, r289095, r289097, r289098, r289104, r289105, r289118: various i2c fixes... Fix numerous issues in iic(4) and iicbus(4): --Allow multiple open iic fds by storing addressing state in cdevpriv --Fix, as much as possible, the baked-in race conditions in the iic ioctl interface by requesting bus ownership on I2CSTART, releasing it on I2CSTOP/I2CRSTCARD, and requiring bus ownership by the current cdevpriv to use the I/O ioctls --Reduce internal iic buffer size and remove 1K read/write limit by iteratively calling iicbus_read/iicbus_write --Eliminate dynamic allocation in I2CWRITE/I2CREAD --Move handling of I2CRDWR to separate function and improve error handling --Add new I2CSADDR ioctl to store address in current cdevpriv so that I2CSTART is not needed for read(2)/write(2) to work --Redesign iicbus_request_bus() and iicbus_release_bus(): --iicbus_request_bus() no longer falls through if the bus is already owned by the requesting device. Multiple threads on the same device may want exclusive access. Also, iicbus_release_bus() was never device-recursive anyway. --Previously, if IICBUS_CALLBACK failed in iicbus_release_bus(), but the following iicbus_poll() call succeeded, IICBUS_CALLBACK would not be issued again --Do not hold iicbus mtx during IICBUS_CALLBACK call. There are several drivers that may sleep in IICBUS_CALLBACK, if IIC_WAIT is passed. --Do not loop in iicbus_request_bus if IICBUS_CALLBACK returns EWOULDBLOCK; instead pass that to the caller so that it can retry if so desired. Bugfix: Exit the transfer loop if any read or write operation fails. Also, perform a stop operation on the bus if there was an error, otherwise the bus will remain hung forever. Consistantly use 'if (error != 0)' style in the function. Mostly rewrite the imx i2c driver. This started out as an attempt to fix one specific problem: the driver didn't check for ACK/NAK after writing a slave address byte to the bus, and some slaves signal that they are busy (such as when completing an internal write to flash memory) by sending a NAK in response to being addressed. Use IIC_EBUSBSY and IIC_BUSERR status values consistantly across all drivers. Make it clearer what each one means in the comments that define them. Add iic2errno(), a helper function to translate IIC_Exxxxx status values to errno values that are at least vaguely equivelent. Also add a new status value, IIC_ERESOURCE, to indicate a failure to acquire memory or other required resources to complete a transaction. Return only IIC_Exxxx status values from iicbus-layer functions. Most of these functions are thin wrappers around calling the hardware-layer driver, but some of them do sanity checks and return an error. Add a short name, IIC_INTRWAIT, for the common case (IIC_INTR | IIC_WAIT). Replace a local sx lock that allowed only one client at a time to access an eeprom device with iicbus_request/release_bus(), which achieves the same effect and also keeps other i2c slave drivers from clashing on the bus. --- sys/arm/freescale/imx/imx_i2c.c | 291 ++++++++++------------- sys/arm/freescale/vybrid/vf_i2c.c | 4 +- sys/arm/samsung/exynos/exynos5_i2c.c | 4 +- sys/dev/iicbus/icee.c | 49 ++-- sys/dev/iicbus/iic.c | 437 +++++++++++++++++++++-------------- sys/dev/iicbus/iic.h | 1 + sys/dev/iicbus/iicbus_if.m | 4 + sys/dev/iicbus/iicoc.c | 2 +- sys/dev/iicbus/iiconf.c | 129 +++++++---- sys/dev/iicbus/iiconf.h | 11 +- sys/dev/pcf/pcf.c | 2 +- sys/powerpc/mpc85xx/i2c.c | 2 +- 12 files changed, 518 insertions(+), 418 deletions(-) diff --git a/sys/arm/freescale/imx/imx_i2c.c b/sys/arm/freescale/imx/imx_i2c.c index abcb014..0249275 100644 --- a/sys/arm/freescale/imx/imx_i2c.c +++ b/sys/arm/freescale/imx/imx_i2c.c @@ -1,6 +1,7 @@ /*- * Copyright (C) 2008-2009 Semihalf, Michal Hajduk * Copyright (c) 2012, 2013 The FreeBSD Foundation + * Copyright (c) 2015 Ian Lepore * All rights reserved. * * Portions of this software were developed by Oleksandr Rybalko @@ -28,6 +29,19 @@ * SUCH DAMAGE. */ +/* + * I2C driver for Freescale i.MX hardware. + * + * Note that the hardware is capable of running as both a master and a slave. + * This driver currently implements only master-mode operations. + * + * This driver supports multi-master i2c busses, by detecting bus arbitration + * loss and returning IIC_EBUSBSY status. Notably, it does not do any kind of + * retries if some other master jumps onto the bus and interrupts one of our + * transfer cycles resulting in arbitration loss in mid-transfer. The caller + * must handle retries in a way that makes sense for the slave being addressed. + */ + #include __FBSDID("$FreeBSD$"); @@ -43,9 +57,6 @@ __FBSDID("$FreeBSD$"); #include #include -#include -#include - #include #include @@ -108,13 +119,6 @@ static struct clkdiv clkdiv_table[] = { { 2560, 0x1d }, { 3072, 0x1e }, { 3840, 0x1f }, {UINT_MAX, 0x1f} }; -#ifdef DEBUG -#define debugf(fmt, args...) do { printf("%s(): ", __func__); \ - printf(fmt,##args); } while (0) -#else -#define debugf(fmt, args...) -#endif - static struct ofw_compat_data compat_data[] = { {"fsl,imx6q-i2c", 1}, {"fsl,imx-i2c", 1}, @@ -125,10 +129,8 @@ struct i2c_softc { device_t dev; device_t iicbus; struct resource *res; - struct mtx mutex; int rid; - bus_space_handle_t bsh; - bus_space_tag_t bst; + sbintime_t byte_time_sbt; }; static phandle_t i2c_get_node(device_t, device_t); @@ -158,7 +160,7 @@ static device_method_t i2c_methods[] = { DEVMETHOD(iicbus_write, i2c_write), DEVMETHOD(iicbus_transfer, iicbus_transfer_gen), - { 0, 0 } + DEVMETHOD_END }; static driver_t i2c_driver = { @@ -184,14 +186,14 @@ static __inline void i2c_write_reg(struct i2c_softc *sc, bus_size_t off, uint8_t val) { - bus_space_write_1(sc->bst, sc->bsh, off, val); + bus_write_1(sc->res, off, val); } static __inline uint8_t i2c_read_reg(struct i2c_softc *sc, bus_size_t off) { - return (bus_space_read_1(sc->bst, sc->bsh, off)); + return (bus_read_1(sc->res, off)); } static __inline void @@ -204,60 +206,77 @@ i2c_flag_set(struct i2c_softc *sc, bus_size_t off, uint8_t mask) i2c_write_reg(sc, off, status); } -/* Wait for transfer interrupt flag */ +/* Wait for bus to become busy or not-busy. */ static int -wait_for_iif(struct i2c_softc *sc) +wait_for_busbusy(struct i2c_softc *sc, int wantbusy) { - int retry; + int retry, srb; retry = 1000; while (retry --) { - if (i2c_read_reg(sc, I2C_STATUS_REG) & I2CSR_MIF) + srb = i2c_read_reg(sc, I2C_STATUS_REG) & I2CSR_MBB; + if ((srb && wantbusy) || (!srb && !wantbusy)) return (IIC_NOERR); - DELAY(10); + DELAY(1); } - return (IIC_ETIMEOUT); } -/* Wait for free bus */ +/* Wait for transfer to complete, optionally check RXAK. */ static int -wait_for_nibb(struct i2c_softc *sc) +wait_for_xfer(struct i2c_softc *sc, int checkack) { - int retry; + int retry, sr; - retry = 1000; + /* + * Sleep for about the time it takes to transfer a byte (with precision + * set to tolerate 5% oversleep). We calculate the approximate byte + * transfer time when we set the bus speed divisor. Slaves are allowed + * to do clock-stretching so the actual transfer time can be larger, but + * this gets the bulk of the waiting out of the way without tying up the + * processor the whole time. + */ + pause_sbt("imxi2c", sc->byte_time_sbt, sc->byte_time_sbt / 20, 0); + + retry = 10000; while (retry --) { - if ((i2c_read_reg(sc, I2C_STATUS_REG) & I2CSR_MBB) == 0) - return (IIC_NOERR); - DELAY(10); + sr = i2c_read_reg(sc, I2C_STATUS_REG); + if (sr & I2CSR_MIF) { + if (sr & I2CSR_MAL) + return (IIC_EBUSERR); + else if (checkack && (sr & I2CSR_RXAK)) + return (IIC_ENOACK); + else + return (IIC_NOERR); + } + DELAY(1); } - return (IIC_ETIMEOUT); } -/* Wait for transfer complete+interrupt flag */ +/* + * Implement the error handling shown in the state diagram of the imx6 reference + * manual. If there was an error, then: + * - Clear master mode (MSTA and MTX). + * - Wait for the bus to become free or for a timeout to happen. + * - Disable the controller. + */ static int -wait_for_icf(struct i2c_softc *sc) +i2c_error_handler(struct i2c_softc *sc, int error) { - int retry; - retry = 1000; - while (retry --) { - - if ((i2c_read_reg(sc, I2C_STATUS_REG) & - (I2CSR_MCF|I2CSR_MIF)) == (I2CSR_MCF|I2CSR_MIF)) - return (IIC_NOERR); - DELAY(10); + if (error != 0) { + i2c_write_reg(sc, I2C_STATUS_REG, 0); + i2c_write_reg(sc, I2C_CONTROL_REG, I2CCR_MEN); + wait_for_busbusy(sc, false); + i2c_write_reg(sc, I2C_CONTROL_REG, 0); } - - return (IIC_ETIMEOUT); + return (error); } static int i2c_probe(device_t dev) { - struct i2c_softc *sc; if (!ofw_bus_status_okay(dev)) return (ENXIO); @@ -265,23 +284,7 @@ i2c_probe(device_t dev) if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0) return (ENXIO); - sc = device_get_softc(dev); - sc->rid = 0; - - sc->res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &sc->rid, - RF_ACTIVE); - if (sc->res == NULL) { - device_printf(dev, "could not allocate resources\n"); - return (ENXIO); - } - - sc->bst = rman_get_bustag(sc->res); - sc->bsh = rman_get_bushandle(sc->res); - - /* Enable I2C */ - i2c_write_reg(sc, I2C_CONTROL_REG, I2CCR_MEN); - bus_release_resource(dev, SYS_RES_MEMORY, sc->rid, sc->res); - device_set_desc(dev, "Freescale i.MX I2C bus controller"); + device_set_desc(dev, "Freescale i.MX I2C"); return (BUS_PROBE_DEFAULT); } @@ -295,28 +298,21 @@ i2c_attach(device_t dev) sc->dev = dev; sc->rid = 0; - mtx_init(&sc->mutex, device_get_nameunit(dev), "I2C", MTX_DEF); - sc->res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &sc->rid, RF_ACTIVE); if (sc->res == NULL) { device_printf(dev, "could not allocate resources"); - mtx_destroy(&sc->mutex); return (ENXIO); } - sc->bst = rman_get_bustag(sc->res); - sc->bsh = rman_get_bushandle(sc->res); - sc->iicbus = device_add_child(dev, "iicbus", -1); if (sc->iicbus == NULL) { device_printf(dev, "could not add iicbus child"); - mtx_destroy(&sc->mutex); return (ENXIO); } bus_generic_attach(dev); - return (IIC_NOERR); + return (0); } static int @@ -327,34 +323,20 @@ i2c_repeated_start(device_t dev, u_char slave, int timeout) sc = device_get_softc(dev); - mtx_lock(&sc->mutex); - - i2c_write_reg(sc, I2C_ADDR_REG, slave); if ((i2c_read_reg(sc, I2C_STATUS_REG) & I2CSR_MBB) == 0) { - mtx_unlock(&sc->mutex); - return (IIC_EBUSBSY); + return (IIC_EBUSERR); } - /* Set repeated start condition */ - DELAY(10); + /* + * Set repeated start condition, delay (per reference manual, min 156nS) + * before writing slave address, wait for ack after write. + */ i2c_flag_set(sc, I2C_CONTROL_REG, I2CCR_RSTA); - DELAY(10); - /* Clear status */ + DELAY(1); i2c_write_reg(sc, I2C_STATUS_REG, 0x0); - /* Write target address - LSB is R/W bit */ i2c_write_reg(sc, I2C_DATA_REG, slave); - - error = wait_for_iif(sc); - - /* Clear status */ - i2c_write_reg(sc, I2C_STATUS_REG, 0x0); - - mtx_unlock(&sc->mutex); - - if (error) - return (error); - - return (IIC_NOERR); + error = wait_for_xfer(sc, true); + return (i2c_error_handler(sc, error)); } static int @@ -365,53 +347,30 @@ i2c_start(device_t dev, u_char slave, int timeout) sc = device_get_softc(dev); - mtx_lock(&sc->mutex); - i2c_write_reg(sc, I2C_ADDR_REG, slave); + i2c_write_reg(sc, I2C_CONTROL_REG, I2CCR_MEN); + DELAY(10); /* Delay for controller to sample bus state. */ if (i2c_read_reg(sc, I2C_STATUS_REG) & I2CSR_MBB) { - mtx_unlock(&sc->mutex); - return (IIC_EBUSBSY); + return (i2c_error_handler(sc, IIC_EBUSERR)); } - - /* Set start condition */ - i2c_write_reg(sc, I2C_CONTROL_REG, - I2CCR_MEN | I2CCR_MSTA | I2CCR_TXAK); - DELAY(100); - i2c_write_reg(sc, I2C_CONTROL_REG, - I2CCR_MEN | I2CCR_MSTA | I2CCR_MTX | I2CCR_TXAK); - /* Clear status */ - i2c_write_reg(sc, I2C_STATUS_REG, 0x0); - /* Write target address - LSB is R/W bit */ + i2c_write_reg(sc, I2C_CONTROL_REG, I2CCR_MEN | I2CCR_MSTA | I2CCR_MTX); + if ((error = wait_for_busbusy(sc, true)) != IIC_NOERR) + return (i2c_error_handler(sc, error)); + i2c_write_reg(sc, I2C_STATUS_REG, 0); i2c_write_reg(sc, I2C_DATA_REG, slave); - - error = wait_for_iif(sc); - - mtx_unlock(&sc->mutex); - if (error) - return (error); - - return (IIC_NOERR); + error = wait_for_xfer(sc, true); + return (i2c_error_handler(sc, error)); } - static int i2c_stop(device_t dev) { struct i2c_softc *sc; sc = device_get_softc(dev); - mtx_lock(&sc->mutex); - i2c_write_reg(sc, I2C_CONTROL_REG, I2CCR_MEN | I2CCR_TXAK); - DELAY(100); - /* Reset controller if bus still busy after STOP */ - if (wait_for_nibb(sc) == IIC_ETIMEOUT) { - i2c_write_reg(sc, I2C_CONTROL_REG, 0); - DELAY(1000); - i2c_write_reg(sc, I2C_CONTROL_REG, I2CCR_MEN | I2CCR_TXAK); - - i2c_write_reg(sc, I2C_STATUS_REG, 0x0); - } - mtx_unlock(&sc->mutex); + i2c_write_reg(sc, I2C_CONTROL_REG, I2CCR_MEN); + wait_for_busbusy(sc, false); + i2c_write_reg(sc, I2C_CONTROL_REG, 0); return (IIC_NOERR); } @@ -434,19 +393,23 @@ i2c_reset(device_t dev, u_char speed, u_char addr, u_char *oldadr) if (clkdiv_table[i].divisor >= div) break; } - div = clkdiv_table[i].regcode; - mtx_lock(&sc->mutex); - i2c_write_reg(sc, I2C_CONTROL_REG, 0x0); - i2c_write_reg(sc, I2C_STATUS_REG, 0x0); - DELAY(1000); + /* + * Calculate roughly how long it will take to transfer a byte (which + * requires 9 clock cycles) at the new bus speed. This value is used to + * pause() while waiting for transfer-complete. With a 66MHz IPG clock + * and the actual i2c bus speeds that leads to, for nominal 100KHz and + * 400KHz bus speeds the transfer times are roughly 104uS and 22uS. + */ + busfreq = ipgfreq / clkdiv_table[i].divisor; + sc->byte_time_sbt = SBT_1US * (9000000 / busfreq); - i2c_write_reg(sc, I2C_FDR_REG, (uint8_t)div); - i2c_write_reg(sc, I2C_CONTROL_REG, I2CCR_MEN); - DELAY(1000); + /* + * Disable the controller (do the reset), and set the new clock divisor. + */ i2c_write_reg(sc, I2C_STATUS_REG, 0x0); - mtx_unlock(&sc->mutex); - + i2c_write_reg(sc, I2C_CONTROL_REG, 0x0); + i2c_write_reg(sc, I2C_FDR_REG, (uint8_t)clkdiv_table[i].regcode); return (IIC_NOERR); } @@ -459,48 +422,42 @@ i2c_read(device_t dev, char *buf, int len, int *read, int last, int delay) sc = device_get_softc(dev); *read = 0; - mtx_lock(&sc->mutex); - if (len) { if (len == 1) i2c_write_reg(sc, I2C_CONTROL_REG, I2CCR_MEN | I2CCR_MSTA | I2CCR_TXAK); - else i2c_write_reg(sc, I2C_CONTROL_REG, I2CCR_MEN | I2CCR_MSTA); - - /* dummy read */ + /* Dummy read to prime the receiver. */ + i2c_write_reg(sc, I2C_STATUS_REG, 0x0); i2c_read_reg(sc, I2C_DATA_REG); - DELAY(1000); } + error = 0; + *read = 0; while (*read < len) { - error = wait_for_icf(sc); - if (error) { - mtx_unlock(&sc->mutex); - return (error); - } + if ((error = wait_for_xfer(sc, false)) != IIC_NOERR) + break; i2c_write_reg(sc, I2C_STATUS_REG, 0x0); - if ((*read == len - 2) && last) { - /* NO ACK on last byte */ - i2c_write_reg(sc, I2C_CONTROL_REG, I2CCR_MEN | - I2CCR_MSTA | I2CCR_TXAK); + if (last) { + if (*read == len - 2) { + /* NO ACK on last byte */ + i2c_write_reg(sc, I2C_CONTROL_REG, I2CCR_MEN | + I2CCR_MSTA | I2CCR_TXAK); + } else if (*read == len - 1) { + /* Transfer done, signal stop. */ + i2c_write_reg(sc, I2C_CONTROL_REG, I2CCR_MEN | + I2CCR_TXAK); + wait_for_busbusy(sc, false); + } } - - if ((*read == len - 1) && last) { - /* Transfer done, remove master bit */ - i2c_write_reg(sc, I2C_CONTROL_REG, I2CCR_MEN | - I2CCR_TXAK); - } - reg = i2c_read_reg(sc, I2C_DATA_REG); *buf++ = reg; (*read)++; } - mtx_unlock(&sc->mutex); - return (IIC_NOERR); + return (i2c_error_handler(sc, error)); } static int @@ -510,22 +467,16 @@ i2c_write(device_t dev, const char *buf, int len, int *sent, int timeout) int error; sc = device_get_softc(dev); - *sent = 0; - mtx_lock(&sc->mutex); + error = 0; + *sent = 0; while (*sent < len) { i2c_write_reg(sc, I2C_STATUS_REG, 0x0); i2c_write_reg(sc, I2C_DATA_REG, *buf++); - - error = wait_for_iif(sc); - if (error) { - mtx_unlock(&sc->mutex); - return (error); - } - + if ((error = wait_for_xfer(sc, true)) != IIC_NOERR) + break; (*sent)++; } - mtx_unlock(&sc->mutex); - return (IIC_NOERR); + return (i2c_error_handler(sc, error)); } diff --git a/sys/arm/freescale/vybrid/vf_i2c.c b/sys/arm/freescale/vybrid/vf_i2c.c index 2eb6726..92a48d7 100644 --- a/sys/arm/freescale/vybrid/vf_i2c.c +++ b/sys/arm/freescale/vybrid/vf_i2c.c @@ -233,7 +233,7 @@ i2c_repeated_start(device_t dev, u_char slave, int timeout) if ((READ1(sc, I2C_IBSR) & IBSR_IBB) == 0) { mtx_unlock(&sc->mutex); - return (IIC_EBUSBSY); + return (IIC_EBUSERR); } /* Set repeated start condition */ @@ -276,7 +276,7 @@ i2c_start(device_t dev, u_char slave, int timeout) if (READ1(sc, I2C_IBSR) & IBSR_IBB) { mtx_unlock(&sc->mutex); vf_i2c_dbg(sc, "cant i2c start: IIC_EBUSBSY\n"); - return (IIC_EBUSBSY); + return (IIC_EBUSERR); } /* Set start condition */ diff --git a/sys/arm/samsung/exynos/exynos5_i2c.c b/sys/arm/samsung/exynos/exynos5_i2c.c index bf7548f..a73beed 100644 --- a/sys/arm/samsung/exynos/exynos5_i2c.c +++ b/sys/arm/samsung/exynos/exynos5_i2c.c @@ -265,8 +265,8 @@ i2c_start(device_t dev, u_char slave, int timeout) error = wait_for_nibb(sc); if (error) { mtx_unlock(&sc->mutex); - DPRINTF("cant i2c start: IIC_EBUSBSY\n"); - return (IIC_EBUSBSY); + DPRINTF("cant i2c start: IIC_EBUSERR\n"); + return (IIC_EBUSERR); } reg = READ1(sc, I2CCON); diff --git a/sys/dev/iicbus/icee.c b/sys/dev/iicbus/icee.c index 2e26d0e..800ec4c 100644 --- a/sys/dev/iicbus/icee.c +++ b/sys/dev/iicbus/icee.c @@ -48,7 +48,7 @@ __FBSDID("$FreeBSD$"); struct icee_softc { device_t sc_dev; /* Myself */ - struct sx sc_lock; /* basically a perimeter lock */ + device_t sc_busdev; /* Parent bus */ struct cdev *cdev; /* user interface */ int addr; int size; /* How big am I? */ @@ -57,12 +57,6 @@ struct icee_softc { int wr_sz; /* What's the write page size */ }; -#define ICEE_LOCK(_sc) sx_xlock(&(_sc)->sc_lock) -#define ICEE_UNLOCK(_sc) sx_xunlock(&(_sc)->sc_lock) -#define ICEE_LOCK_INIT(_sc) sx_init(&_sc->sc_lock, "icee") -#define ICEE_LOCK_DESTROY(_sc) sx_destroy(&_sc->sc_lock); -#define ICEE_ASSERT_LOCKED(_sc) sx_assert(&_sc->sc_lock, SA_XLOCKED); -#define ICEE_ASSERT_UNLOCKED(_sc) sx_assert(&_sc->sc_lock, SA_UNLOCKED); #define CDEV2SOFTC(dev) ((dev)->si_drv1) /* cdev routines */ @@ -84,7 +78,7 @@ static struct cdevsw icee_cdevsw = static int icee_probe(device_t dev) { - /* XXX really probe? -- not until we know the size... */ + device_set_desc(dev, "I2C EEPROM"); return (BUS_PROBE_NOWILDCARD); } @@ -97,6 +91,7 @@ icee_attach(device_t dev) int dunit, err; sc->sc_dev = dev; + sc->sc_busdev = device_get_parent(sc->sc_dev); sc->addr = iicbus_get_addr(dev); err = 0; dname = device_get_name(dev); @@ -117,8 +112,7 @@ icee_attach(device_t dev) goto out; } sc->cdev->si_drv1 = sc; - ICEE_LOCK_INIT(sc); -out:; +out: return (err); } @@ -126,7 +120,7 @@ static int icee_open(struct cdev *dev, int oflags, int devtype, struct thread *td) { - return (0); + return (0); } static int @@ -155,7 +149,9 @@ icee_read(struct cdev *dev, struct uio *uio, int ioflag) return (EIO); if (sc->type != 8 && sc->type != 16) return (EINVAL); - ICEE_LOCK(sc); + error = iicbus_request_bus(sc->sc_busdev, sc->sc_dev, IIC_INTRWAIT); + if (error!= 0) + return (iic2errno(error)); slave = error = 0; while (uio->uio_resid > 0) { if (uio->uio_offset >= sc->size) @@ -180,13 +176,15 @@ icee_read(struct cdev *dev, struct uio *uio, int ioflag) for (i = 0; i < 2; i++) msgs[i].slave = slave; error = iicbus_transfer(sc->sc_dev, msgs, 2); - if (error) + if (error) { + error = iic2errno(error); break; + } error = uiomove(data, len, uio); if (error) break; } - ICEE_UNLOCK(sc); + iicbus_release_bus(sc->sc_busdev, sc->sc_dev); return (error); } @@ -214,7 +212,10 @@ icee_write(struct cdev *dev, struct uio *uio, int ioflag) return (EIO); if (sc->type != 8 && sc->type != 16) return (EINVAL); - ICEE_LOCK(sc); + + error = iicbus_request_bus(sc->sc_busdev, sc->sc_dev, IIC_INTRWAIT); + if (error!= 0) + return (iic2errno(error)); slave = error = 0; while (uio->uio_resid > 0) { if (uio->uio_offset >= sc->size) @@ -239,22 +240,22 @@ icee_write(struct cdev *dev, struct uio *uio, int ioflag) if (error) break; error = iicbus_transfer(sc->sc_dev, wr, 1); - if (error) + if (error) { + error = iic2errno(error); break; - // Now wait for the write to be done by trying to read - // the part. + } + /* Read after write to wait for write-done. */ waitlimit = 10000; rd[0].slave = slave; - do - { - error = iicbus_transfer(sc->sc_dev, rd, 1); + do { + error = iicbus_transfer(sc->sc_dev, rd, 1); } while (waitlimit-- > 0 && error != 0); if (error) { - printf("waiting for write failed %d\n", error); - break; + error = iic2errno(error); + break; } } - ICEE_UNLOCK(sc); + iicbus_release_bus(sc->sc_busdev, sc->sc_dev); return error; } diff --git a/sys/dev/iicbus/iic.c b/sys/dev/iicbus/iic.c index 16d113ee..84e1314 100644 --- a/sys/dev/iicbus/iic.c +++ b/sys/dev/iicbus/iic.c @@ -37,6 +37,7 @@ #include #include #include +#include #include #include @@ -44,28 +45,32 @@ #include "iicbus_if.h" -#define BUFSIZE 1024 - struct iic_softc { - device_t sc_dev; - u_char sc_addr; /* 7 bit address on iicbus */ - int sc_count; /* >0 if device opened */ - - char sc_buffer[BUFSIZE]; /* output buffer */ - char sc_inbuf[BUFSIZE]; /* input buffer */ - struct cdev *sc_devnode; - struct sx sc_lock; }; -#define IIC_LOCK(sc) sx_xlock(&(sc)->sc_lock) -#define IIC_UNLOCK(sc) sx_xunlock(&(sc)->sc_lock) +struct iic_cdevpriv { + struct sx lock; + struct iic_softc *sc; + bool started; + uint8_t addr; +}; + + +#define IIC_LOCK(cdp) sx_xlock(&(cdp)->lock) +#define IIC_UNLOCK(cdp) sx_xunlock(&(cdp)->lock) + +static MALLOC_DEFINE(M_IIC, "iic", "I2C device data"); static int iic_probe(device_t); static int iic_attach(device_t); static int iic_detach(device_t); static void iic_identify(driver_t *driver, device_t parent); +static void iicdtor(void *data); +static int iicuio_move(struct iic_cdevpriv *priv, struct uio *uio, int last); +static int iicuio(struct cdev *dev, struct uio *uio, int ioflag); +static int iicrdwr(struct iic_cdevpriv *priv, struct iic_rdwr_data *d, int flags); static devclass_t iic_devclass; @@ -89,18 +94,13 @@ static driver_t iic_driver = { }; static d_open_t iicopen; -static d_close_t iicclose; -static d_write_t iicwrite; -static d_read_t iicread; static d_ioctl_t iicioctl; static struct cdevsw iic_cdevsw = { .d_version = D_VERSION, - .d_flags = D_TRACKCLOSE, .d_open = iicopen, - .d_close = iicclose, - .d_read = iicread, - .d_write = iicwrite, + .d_read = iicuio, + .d_write = iicuio, .d_ioctl = iicioctl, .d_name = "iic", }; @@ -127,16 +127,15 @@ iic_probe(device_t dev) static int iic_attach(device_t dev) { - struct iic_softc *sc = (struct iic_softc *)device_get_softc(dev); + struct iic_softc *sc; + sc = device_get_softc(dev); sc->sc_dev = dev; - sx_init(&sc->sc_lock, "iic"); sc->sc_devnode = make_dev(&iic_cdevsw, device_get_unit(dev), UID_ROOT, GID_WHEEL, 0600, "iic%d", device_get_unit(dev)); if (sc->sc_devnode == NULL) { device_printf(dev, "failed to create character device\n"); - sx_destroy(&sc->sc_lock); return (ENXIO); } sc->sc_devnode->si_drv1 = sc; @@ -147,11 +146,12 @@ iic_attach(device_t dev) static int iic_detach(device_t dev) { - struct iic_softc *sc = (struct iic_softc *)device_get_softc(dev); + struct iic_softc *sc; + + sc = device_get_softc(dev); if (sc->sc_devnode) destroy_dev(sc->sc_devnode); - sx_destroy(&sc->sc_lock); return (0); } @@ -159,238 +159,331 @@ iic_detach(device_t dev) static int iicopen(struct cdev *dev, int flags, int fmt, struct thread *td) { - struct iic_softc *sc = dev->si_drv1; + struct iic_cdevpriv *priv; + int error; - IIC_LOCK(sc); - if (sc->sc_count > 0) { - IIC_UNLOCK(sc); - return (EBUSY); - } + priv = malloc(sizeof(*priv), M_IIC, M_WAITOK | M_ZERO); - sc->sc_count++; - IIC_UNLOCK(sc); + sx_init(&priv->lock, "iic"); + priv->sc = dev->si_drv1; - return (0); + error = devfs_set_cdevpriv(priv, iicdtor); + if (error != 0) + free(priv, M_IIC); + + return (error); } -static int -iicclose(struct cdev *dev, int flags, int fmt, struct thread *td) +static void +iicdtor(void *data) { - struct iic_softc *sc = dev->si_drv1; + device_t iicdev, parent; + struct iic_cdevpriv *priv; - IIC_LOCK(sc); - if (!sc->sc_count) { - /* XXX: I don't think this can happen. */ - IIC_UNLOCK(sc); - return (EINVAL); - } + priv = data; + KASSERT(priv != NULL, ("iic cdevpriv should not be NULL!")); - sc->sc_count--; + iicdev = priv->sc->sc_dev; + parent = device_get_parent(iicdev); - if (sc->sc_count < 0) - panic("%s: iic_count < 0!", __func__); - IIC_UNLOCK(sc); + if (priv->started) { + iicbus_stop(parent); + iicbus_reset(parent, IIC_UNKNOWN, 0, NULL); + iicbus_release_bus(parent, iicdev); + } - return (0); + sx_destroy(&priv->lock); + free(priv, M_IIC); } static int -iicwrite(struct cdev *dev, struct uio * uio, int ioflag) +iicuio_move(struct iic_cdevpriv *priv, struct uio *uio, int last) { - struct iic_softc *sc = dev->si_drv1; - device_t iicdev = sc->sc_dev; - int sent, error, count; - - IIC_LOCK(sc); - if (!sc->sc_addr) { - IIC_UNLOCK(sc); - return (EINVAL); + device_t parent; + int error, num_bytes, transferred_bytes, written_bytes; + char buffer[128]; + + parent = device_get_parent(priv->sc->sc_dev); + error = 0; + + /* + * We can only transfer up to sizeof(buffer) bytes in 1 shot, so loop until + * everything has been transferred. + */ + while ((error == 0) && (uio->uio_resid > 0)) { + + num_bytes = MIN(uio->uio_resid, sizeof(buffer)); + transferred_bytes = 0; + + if (uio->uio_rw == UIO_WRITE) { + error = uiomove(buffer, num_bytes, uio); + + while ((error == 0) && (transferred_bytes < num_bytes)) { + written_bytes = 0; + error = iicbus_write(parent, &buffer[transferred_bytes], + num_bytes - transferred_bytes, &written_bytes, 0); + transferred_bytes += written_bytes; + } + + } else if (uio->uio_rw == UIO_READ) { + error = iicbus_read(parent, buffer, + num_bytes, &transferred_bytes, + ((uio->uio_resid <= sizeof(buffer)) ? last : 0), 0); + if (error == 0) + error = uiomove(buffer, transferred_bytes, uio); + } } - if (sc->sc_count == 0) { - /* XXX: I don't think this can happen. */ - IIC_UNLOCK(sc); - return (EINVAL); - } + return (error); +} - error = iicbus_request_bus(device_get_parent(iicdev), iicdev, - IIC_DONTWAIT); - if (error) { - IIC_UNLOCK(sc); +static int +iicuio(struct cdev *dev, struct uio *uio, int ioflag) +{ + device_t parent; + struct iic_cdevpriv *priv; + int error; + uint8_t addr; + + priv = NULL; + error = devfs_get_cdevpriv((void**)&priv); + + if (error != 0) return (error); + KASSERT(priv != NULL, ("iic cdevpriv should not be NULL!")); + + IIC_LOCK(priv); + if (priv->started || (priv->addr == 0)) { + IIC_UNLOCK(priv); + return (ENXIO); } + parent = device_get_parent(priv->sc->sc_dev); - count = min(uio->uio_resid, BUFSIZE); - error = uiomove(sc->sc_buffer, count, uio); - if (error) { - IIC_UNLOCK(sc); + error = iicbus_request_bus(parent, priv->sc->sc_dev, + (ioflag & O_NONBLOCK) ? IIC_DONTWAIT : (IIC_WAIT | IIC_INTR)); + if (error != 0) { + IIC_UNLOCK(priv); return (error); } - error = iicbus_block_write(device_get_parent(iicdev), sc->sc_addr, - sc->sc_buffer, count, &sent); + if (uio->uio_rw == UIO_READ) + addr = priv->addr | LSB; + else + addr = priv->addr & ~LSB; + + error = iicbus_start(parent, addr, 0); + if (error != 0) + { + iicbus_release_bus(parent, priv->sc->sc_dev); + IIC_UNLOCK(priv); + return (error); + } - iicbus_release_bus(device_get_parent(iicdev), iicdev); - IIC_UNLOCK(sc); + error = iicuio_move(priv, uio, IIC_LAST_READ); + iicbus_stop(parent); + iicbus_release_bus(parent, priv->sc->sc_dev); + IIC_UNLOCK(priv); return (error); } static int -iicread(struct cdev *dev, struct uio * uio, int ioflag) +iicrdwr(struct iic_cdevpriv *priv, struct iic_rdwr_data *d, int flags) { - struct iic_softc *sc = dev->si_drv1; - device_t iicdev = sc->sc_dev; - int len, error = 0; - int bufsize; - - IIC_LOCK(sc); - if (!sc->sc_addr) { - IIC_UNLOCK(sc); - return (EINVAL); - } + struct iic_msg *buf, *m; + void **usrbufs; + device_t iicdev, parent; + int error, i; - if (sc->sc_count == 0) { - /* XXX: I don't think this can happen. */ - IIC_UNLOCK(sc); - return (EINVAL); - } + iicdev = priv->sc->sc_dev; + parent = device_get_parent(iicdev); + error = 0; - error = iicbus_request_bus(device_get_parent(iicdev), iicdev, - IIC_DONTWAIT); - if (error) { - IIC_UNLOCK(sc); - return (error); - } + buf = malloc(sizeof(*d->msgs) * d->nmsgs, M_IIC, M_WAITOK); - /* max amount of data to read */ - len = min(uio->uio_resid, BUFSIZE); + error = copyin(d->msgs, buf, sizeof(*d->msgs) * d->nmsgs); - error = iicbus_block_read(device_get_parent(iicdev), sc->sc_addr, - sc->sc_inbuf, len, &bufsize); - if (error) { - IIC_UNLOCK(sc); - return (error); + /* Alloc kernel buffers for userland data, copyin write data */ + usrbufs = malloc(sizeof(void *) * d->nmsgs, M_IIC, M_WAITOK | M_ZERO); + + for (i = 0; i < d->nmsgs; i++) { + m = &(buf[i]); + usrbufs[i] = m->buf; + + /* + * At least init the buffer to NULL so we can safely free() it later. + * If the copyin() to buf failed, don't try to malloc bogus m->len. + */ + m->buf = NULL; + if (error != 0) + continue; + m->buf = malloc(m->len, M_IIC, M_WAITOK); + if (!(m->flags & IIC_M_RD)) + error = copyin(usrbufs[i], m->buf, m->len); } - if (bufsize > uio->uio_resid) - panic("%s: too much data read!", __func__); + if (error == 0) + error = iicbus_request_bus(parent, iicdev, + (flags & O_NONBLOCK) ? IIC_DONTWAIT : (IIC_WAIT | IIC_INTR)); - iicbus_release_bus(device_get_parent(iicdev), iicdev); + if (error == 0) { + error = iicbus_transfer(iicdev, buf, d->nmsgs); + iicbus_release_bus(parent, iicdev); + } + + /* Copyout all read segments, free up kernel buffers */ + for (i = 0; i < d->nmsgs; i++) { + m = &(buf[i]); + if ((error == 0) && (m->flags & IIC_M_RD)) + error = copyout(m->buf, usrbufs[i], m->len); + free(m->buf, M_IIC); + } - error = uiomove(sc->sc_inbuf, bufsize, uio); - IIC_UNLOCK(sc); + free(usrbufs, M_IIC); + free(buf, M_IIC); return (error); } static int iicioctl(struct cdev *dev, u_long cmd, caddr_t data, int flags, struct thread *td) { - struct iic_softc *sc = dev->si_drv1; - device_t iicdev = sc->sc_dev; - device_t parent = device_get_parent(iicdev); - struct iiccmd *s = (struct iiccmd *)data; - struct iic_rdwr_data *d = (struct iic_rdwr_data *)data; - struct iic_msg *m; - int error, count, i; - char *buf = NULL; - void **usrbufs = NULL; - - if ((error = iicbus_request_bus(parent, iicdev, - (flags & O_NONBLOCK) ? IIC_DONTWAIT : (IIC_WAIT | IIC_INTR)))) + device_t parent, iicdev; + struct iiccmd *s; + struct uio ubuf; + struct iovec uvec; + struct iic_cdevpriv *priv; + int error; + + s = (struct iiccmd *)data; + error = devfs_get_cdevpriv((void**)&priv); + if (error != 0) return (error); + KASSERT(priv != NULL, ("iic cdevpriv should not be NULL!")); + + iicdev = priv->sc->sc_dev; + parent = device_get_parent(iicdev); + IIC_LOCK(priv); + + switch (cmd) { case I2CSTART: - IIC_LOCK(sc); - error = iicbus_start(parent, s->slave, 0); + if (priv->started) { + error = EINVAL; + break; + } + error = iicbus_request_bus(parent, iicdev, + (flags & O_NONBLOCK) ? IIC_DONTWAIT : (IIC_WAIT | IIC_INTR)); - /* - * Implicitly set the chip addr to the slave addr passed as - * parameter. Consequently, start/stop shall be called before - * the read or the write of a block. - */ - if (!error) - sc->sc_addr = s->slave; - IIC_UNLOCK(sc); + if (error == 0) + error = iicbus_start(parent, s->slave, 0); + + if (error == 0) { + priv->addr = s->slave; + priv->started = true; + } else + iicbus_release_bus(parent, iicdev); break; case I2CSTOP: - error = iicbus_stop(parent); + if (priv->started) { + error = iicbus_stop(parent); + iicbus_release_bus(parent, iicdev); + priv->started = false; + } + break; case I2CRSTCARD: - error = iicbus_reset(parent, IIC_UNKNOWN, 0, NULL); /* - * Ignore IIC_ENOADDR as it only means we have a master-only - * controller. - */ - if (error == IIC_ENOADDR) - error = 0; + * Bus should be owned before we reset it. + * We allow the bus to be already owned as the result of an in-progress + * sequence; however, bus reset will always be followed by release + * (a new start is presumably needed for I/O anyway). */ + if (!priv->started) + error = iicbus_request_bus(parent, iicdev, + (flags & O_NONBLOCK) ? IIC_DONTWAIT : (IIC_WAIT | IIC_INTR)); + + if (error == 0) { + error = iicbus_reset(parent, IIC_UNKNOWN, 0, NULL); + /* + * Ignore IIC_ENOADDR as it only means we have a master-only + * controller. + */ + if (error == IIC_ENOADDR) + error = 0; + + iicbus_release_bus(parent, iicdev); + priv->started = false; + } break; case I2CWRITE: - if (s->count <= 0) { + if (!priv->started) { error = EINVAL; break; } - buf = malloc((unsigned long)s->count, M_TEMP, M_WAITOK); - error = copyin(s->buf, buf, s->count); - if (error) - break; - error = iicbus_write(parent, buf, s->count, &count, 10); + uvec.iov_base = s->buf; + uvec.iov_len = s->count; + ubuf.uio_iov = &uvec; + ubuf.uio_iovcnt = 1; + ubuf.uio_segflg = UIO_USERSPACE; + ubuf.uio_td = td; + ubuf.uio_resid = s->count; + ubuf.uio_offset = 0; + ubuf.uio_rw = UIO_WRITE; + error = iicuio_move(priv, &ubuf, 0); break; case I2CREAD: - if (s->count <= 0) { + if (!priv->started) { error = EINVAL; break; } - buf = malloc((unsigned long)s->count, M_TEMP, M_WAITOK); - error = iicbus_read(parent, buf, s->count, &count, s->last, 10); - if (error) - break; - error = copyout(buf, s->buf, s->count); + uvec.iov_base = s->buf; + uvec.iov_len = s->count; + ubuf.uio_iov = &uvec; + ubuf.uio_iovcnt = 1; + ubuf.uio_segflg = UIO_USERSPACE; + ubuf.uio_td = td; + ubuf.uio_resid = s->count; + ubuf.uio_offset = 0; + ubuf.uio_rw = UIO_READ; + error = iicuio_move(priv, &ubuf, s->last); break; case I2CRDWR: - buf = malloc(sizeof(*d->msgs) * d->nmsgs, M_TEMP, M_WAITOK); - error = copyin(d->msgs, buf, sizeof(*d->msgs) * d->nmsgs); - if (error) + /* + * The rdwr list should be a self-contained set of + * transactions. Fail if another transaction is in progress. + */ + if (priv->started) { + error = EINVAL; break; - /* Alloc kernel buffers for userland data, copyin write data */ - usrbufs = malloc(sizeof(void *) * d->nmsgs, M_TEMP, M_ZERO | M_WAITOK); - for (i = 0; i < d->nmsgs; i++) { - m = &((struct iic_msg *)buf)[i]; - usrbufs[i] = m->buf; - m->buf = malloc(m->len, M_TEMP, M_WAITOK); - if (!(m->flags & IIC_M_RD)) - copyin(usrbufs[i], m->buf, m->len); - } - error = iicbus_transfer(iicdev, (struct iic_msg *)buf, d->nmsgs); - /* Copyout all read segments, free up kernel buffers */ - for (i = 0; i < d->nmsgs; i++) { - m = &((struct iic_msg *)buf)[i]; - if (m->flags & IIC_M_RD) - copyout(m->buf, usrbufs[i], m->len); - free(m->buf, M_TEMP); } - free(usrbufs, M_TEMP); + + error = iicrdwr(priv, (struct iic_rdwr_data *)data, flags); + break; case I2CRPTSTART: + if (!priv->started) { + error = EINVAL; + break; + } error = iicbus_repeated_start(parent, s->slave, 0); break; + case I2CSADDR: + priv->addr = *((uint8_t*)data); + break; + default: error = ENOTTY; } - iicbus_release_bus(parent, iicdev); - - if (buf != NULL) - free(buf, M_TEMP); + IIC_UNLOCK(priv); return (error); } diff --git a/sys/dev/iicbus/iic.h b/sys/dev/iicbus/iic.h index ab58abf..ba98d28 100644 --- a/sys/dev/iicbus/iic.h +++ b/sys/dev/iicbus/iic.h @@ -63,5 +63,6 @@ struct iic_rdwr_data { #define I2CREAD _IOW('i', 5, struct iiccmd) /* receive data */ #define I2CRDWR _IOW('i', 6, struct iic_rdwr_data) /* General read/write interface */ #define I2CRPTSTART _IOW('i', 7, struct iiccmd) /* repeated start */ +#define I2CSADDR _IOW('i', 8, uint8_t) /* set slave address for future I/O */ #endif diff --git a/sys/dev/iicbus/iicbus_if.m b/sys/dev/iicbus/iicbus_if.m index 120b5e7..3f58168 100644 --- a/sys/dev/iicbus/iicbus_if.m +++ b/sys/dev/iicbus/iicbus_if.m @@ -51,6 +51,10 @@ METHOD int intr { # # iicbus callback +# Request ownership of bus +# index: IIC_REQUEST_BUS or IIC_RELEASE_BUS +# data: pointer to int containing IIC_WAIT or IIC_DONTWAIT and either IIC_INTR or IIC_NOINTR +# This function is allowed to sleep if *data contains IIC_WAIT. # METHOD int callback { device_t dev; diff --git a/sys/dev/iicbus/iicoc.c b/sys/dev/iicbus/iicoc.c index de17e74..45f1692 100644 --- a/sys/dev/iicbus/iicoc.c +++ b/sys/dev/iicbus/iicoc.c @@ -236,7 +236,7 @@ iicoc_detach(device_t dev) static int iicoc_start(device_t dev, u_char slave, int timeout) { - int error = IIC_EBUSBSY; + int error = IIC_EBUSERR; struct iicoc_softc *sc; sc = device_get_softc(dev); diff --git a/sys/dev/iicbus/iiconf.c b/sys/dev/iicbus/iiconf.c index 940760b..e28d341 100644 --- a/sys/dev/iicbus/iiconf.c +++ b/sys/dev/iicbus/iiconf.c @@ -40,6 +40,28 @@ __FBSDID("$FreeBSD$"); #include "iicbus_if.h" /* + * Translate IIC_Exxxxx status values to vaguely-equivelent errno values. + */ +int +iic2errno(int iic_status) +{ + switch (iic_status) { + case IIC_NOERR: return (0); + case IIC_EBUSERR: return (EALREADY); + case IIC_ENOACK: return (EIO); + case IIC_ETIMEOUT: return (ETIMEDOUT); + case IIC_EBUSBSY: return (EWOULDBLOCK); + case IIC_ESTATUS: return (EPROTO); + case IIC_EUNDERFLOW: return (EIO); + case IIC_EOVERFLOW: return (EOVERFLOW); + case IIC_ENOTSUPP: return (EOPNOTSUPP); + case IIC_ENOADDR: return (EADDRNOTAVAIL); + case IIC_ERESOURCE: return (ENOMEM); + default: return (EIO); + } +} + +/* * iicbus_intr() */ void @@ -70,8 +92,7 @@ iicbus_poll(struct iicbus_softc *sc, int how) break; default: - return (EWOULDBLOCK); - break; + return (IIC_EBUSBSY); } return (error); @@ -90,31 +111,32 @@ iicbus_request_bus(device_t bus, device_t dev, int how) struct iicbus_softc *sc = (struct iicbus_softc *)device_get_softc(bus); int error = 0; - /* first, ask the underlying layers if the request is ok */ IICBUS_LOCK(sc); - do { - error = IICBUS_CALLBACK(device_get_parent(bus), - IIC_REQUEST_BUS, (caddr_t)&how); - if (error) - error = iicbus_poll(sc, how); - } while (error == EWOULDBLOCK); - - while (!error) { - if (sc->owner && sc->owner != dev) { - error = iicbus_poll(sc, how); - } else { - sc->owner = dev; + while ((error == 0) && (sc->owner != NULL)) + error = iicbus_poll(sc, how); + + if (error == 0) { + sc->owner = dev; + /* + * Drop the lock around the call to the bus driver. + * This call should be allowed to sleep in the IIC_WAIT case. + * Drivers might also need to grab locks that would cause LOR + * if our lock is held. + */ + IICBUS_UNLOCK(sc); + /* Ask the underlying layers if the request is ok */ + error = IICBUS_CALLBACK(device_get_parent(bus), + IIC_REQUEST_BUS, (caddr_t)&how); + IICBUS_LOCK(sc); - IICBUS_UNLOCK(sc); - return (0); + if (error != 0) { + sc->owner = NULL; + wakeup_one(sc); } - - /* free any allocated resource */ - if (error) - IICBUS_CALLBACK(device_get_parent(bus), IIC_RELEASE_BUS, - (caddr_t)&how); } + + IICBUS_UNLOCK(sc); return (error); @@ -131,26 +153,33 @@ iicbus_release_bus(device_t bus, device_t dev) struct iicbus_softc *sc = (struct iicbus_softc *)device_get_softc(bus); int error; - /* first, ask the underlying layers if the release is ok */ - error = IICBUS_CALLBACK(device_get_parent(bus), IIC_RELEASE_BUS, NULL); - - if (error) - return (error); - IICBUS_LOCK(sc); if (sc->owner != dev) { IICBUS_UNLOCK(sc); - return (EACCES); + return (IIC_EBUSBSY); } - sc->owner = NULL; - - /* wakeup waiting processes */ - wakeup(sc); + /* + * Drop the lock around the call to the bus driver. + * This call should be allowed to sleep in the IIC_WAIT case. + * Drivers might also need to grab locks that would cause LOR + * if our lock is held. + */ IICBUS_UNLOCK(sc); + /* Ask the underlying layers if the release is ok */ + error = IICBUS_CALLBACK(device_get_parent(bus), IIC_RELEASE_BUS, NULL); - return (0); + if (error == 0) { + IICBUS_LOCK(sc); + sc->owner = NULL; + + /* wakeup a waiting thread */ + wakeup_one(sc); + IICBUS_UNLOCK(sc); + } + + return (error); } /* @@ -178,7 +207,7 @@ iicbus_start(device_t bus, u_char slave, int timeout) int error = 0; if (sc->started) - return (EINVAL); /* bus already started */ + return (IIC_ESTATUS); /* protocol error, bus already started */ if (!(error = IICBUS_START(device_get_parent(bus), slave, timeout))) sc->started = slave; @@ -200,7 +229,7 @@ iicbus_repeated_start(device_t bus, u_char slave, int timeout) int error = 0; if (!sc->started) - return (EINVAL); /* bus should have been already started */ + return (IIC_ESTATUS); /* protocol error, bus not started */ if (!(error = IICBUS_REPEATED_START(device_get_parent(bus), slave, timeout))) sc->started = slave; @@ -222,7 +251,7 @@ iicbus_stop(device_t bus) int error = 0; if (!sc->started) - return (EINVAL); /* bus not started */ + return (IIC_ESTATUS); /* protocol error, bus not started */ error = IICBUS_STOP(device_get_parent(bus)); @@ -245,7 +274,7 @@ iicbus_write(device_t bus, const char *buf, int len, int *sent, int timeout) /* a slave must have been started for writing */ if (sc->started == 0 || (sc->strict != 0 && (sc->started & LSB) != 0)) - return (EINVAL); + return (IIC_ESTATUS); return (IICBUS_WRITE(device_get_parent(bus), buf, len, sent, timeout)); } @@ -263,7 +292,7 @@ iicbus_read(device_t bus, char *buf, int len, int *read, int last, int delay) /* a slave must have been started for reading */ if (sc->started == 0 || (sc->strict != 0 && (sc->started & LSB) == 0)) - return (EINVAL); + return (IIC_ESTATUS); return (IICBUS_READ(device_get_parent(bus), buf, len, read, last, delay)); } @@ -276,9 +305,14 @@ iicbus_read(device_t bus, char *buf, int len, int *read, int last, int delay) int iicbus_write_byte(device_t bus, char byte, int timeout) { + struct iicbus_softc *sc = device_get_softc(bus); char data = byte; int sent; + /* a slave must have been started for writing */ + if (sc->started == 0 || (sc->strict != 0 && (sc->started & LSB) != 0)) + return (IIC_ESTATUS); + return (iicbus_write(bus, &data, 1, &sent, timeout)); } @@ -290,8 +324,13 @@ iicbus_write_byte(device_t bus, char byte, int timeout) int iicbus_read_byte(device_t bus, char *byte, int timeout) { + struct iicbus_softc *sc = device_get_softc(bus); int read; + /* a slave must have been started for reading */ + if (sc->started == 0 || (sc->strict != 0 && (sc->started & LSB) == 0)) + return (IIC_ESTATUS); + return (iicbus_read(bus, byte, 1, &read, IIC_LAST_READ, timeout)); } @@ -352,6 +391,7 @@ iicbus_block_read(device_t bus, u_char slave, char *buf, int len, int *read) int iicbus_transfer(device_t bus, struct iic_msg *msgs, uint32_t nmsgs) { + return (IICBUS_TRANSFER(device_get_parent(bus), msgs, nmsgs)); } @@ -368,10 +408,10 @@ iicbus_transfer_gen(device_t dev, struct iic_msg *msgs, uint32_t nmsgs) bool nostop; if ((error = device_get_children(dev, &children, &nkid)) != 0) - return (error); + return (IIC_ERESOURCE); if (nkid != 1) { free(children, M_TEMP); - return (EIO); + return (IIC_ENOTSUPP); } bus = children[0]; rpstart = 0; @@ -390,8 +430,7 @@ iicbus_transfer_gen(device_t dev, struct iic_msg *msgs, uint32_t nmsgs) else error = iicbus_start(bus, addr, 0); } - - if (error) + if (error != 0) break; if (msgs[i].flags & IIC_M_RD) @@ -400,6 +439,8 @@ iicbus_transfer_gen(device_t dev, struct iic_msg *msgs, uint32_t nmsgs) else error = iicbus_write(bus, msgs[i].buf, msgs[i].len, &lenwrote, 0); + if (error != 0) + break; if ((msgs[i].flags & IIC_M_NOSTOP) != 0 || (nostop && i + 1 < nmsgs)) { @@ -409,5 +450,7 @@ iicbus_transfer_gen(device_t dev, struct iic_msg *msgs, uint32_t nmsgs) iicbus_stop(bus); } } + if (error != 0 && !nostop) + iicbus_stop(bus); return (error); } diff --git a/sys/dev/iicbus/iiconf.h b/sys/dev/iicbus/iiconf.h index 092ba8d..aca0137 100644 --- a/sys/dev/iicbus/iiconf.h +++ b/sys/dev/iicbus/iiconf.h @@ -43,6 +43,7 @@ #define IIC_NOINTR 0 #define IIC_WAIT 0x1 #define IIC_INTR 0x2 +#define IIC_INTRWAIT (IIC_INTR | IIC_WAIT) /* * i2c modes @@ -82,16 +83,22 @@ * adapter layer errors */ #define IIC_NOERR 0x0 /* no error occured */ -#define IIC_EBUSERR 0x1 /* bus error */ +#define IIC_EBUSERR 0x1 /* bus error (hardware not in expected state) */ #define IIC_ENOACK 0x2 /* ack not received until timeout */ #define IIC_ETIMEOUT 0x3 /* timeout */ -#define IIC_EBUSBSY 0x4 /* bus busy */ +#define IIC_EBUSBSY 0x4 /* bus busy (reserved by another client) */ #define IIC_ESTATUS 0x5 /* status error */ #define IIC_EUNDERFLOW 0x6 /* slave ready for more data */ #define IIC_EOVERFLOW 0x7 /* too much data */ #define IIC_ENOTSUPP 0x8 /* request not supported */ #define IIC_ENOADDR 0x9 /* no address assigned to the interface */ +#define IIC_ERESOURCE 0xa /* resources (memory, whatever) unavailable */ +/* + * Note that all iicbus functions return IIC_Exxxxx status values, + * except iic2errno() (obviously) and iicbus_started() (returns bool). + */ +extern int iic2errno(int); extern int iicbus_request_bus(device_t, device_t, int); extern int iicbus_release_bus(device_t, device_t); extern device_t iicbus_alloc_bus(device_t); diff --git a/sys/dev/pcf/pcf.c b/sys/dev/pcf/pcf.c index 55e0346..f9252b5 100644 --- a/sys/dev/pcf/pcf.c +++ b/sys/dev/pcf/pcf.c @@ -170,7 +170,7 @@ pcf_start(device_t dev, u_char slave, int timeout) printf("pcf: busy!\n"); #endif PCF_UNLOCK(sc); - return (IIC_EBUSBSY); + return (IIC_EBUSERR); } /* set slave address to PCF. Last bit (LSB) must be set correctly diff --git a/sys/powerpc/mpc85xx/i2c.c b/sys/powerpc/mpc85xx/i2c.c index f21c845..e02a08b 100644 --- a/sys/powerpc/mpc85xx/i2c.c +++ b/sys/powerpc/mpc85xx/i2c.c @@ -284,7 +284,7 @@ i2c_start(device_t dev, u_char slave, int timeout) debugf("bus busy"); mtx_unlock(&sc->mutex); i2c_stop(dev); - return (IIC_EBUSBSY); + return (IIC_EBUSERR); } /* Set start condition */ -- cgit v1.1