From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58920) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gRNPz-0001zq-Vf for qemu-devel@nongnu.org; Mon, 26 Nov 2018 15:23:48 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gRNPv-0000E5-7w for qemu-devel@nongnu.org; Mon, 26 Nov 2018 15:23:43 -0500 Received: from mail-wm1-f67.google.com ([209.85.128.67]:38118) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1gRNPu-0000Da-Th for qemu-devel@nongnu.org; Mon, 26 Nov 2018 15:23:39 -0500 Received: by mail-wm1-f67.google.com with SMTP id k198so19985288wmd.3 for ; Mon, 26 Nov 2018 12:23:37 -0800 (PST) References: <20181126200435.23408-1-minyard@acm.org> <20181126200435.23408-3-minyard@acm.org> From: =?UTF-8?Q?Philippe_Mathieu-Daud=c3=a9?= Message-ID: Date: Mon, 26 Nov 2018 21:23:35 +0100 MIME-Version: 1.0 In-Reply-To: <20181126200435.23408-3-minyard@acm.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Subject: Re: [Qemu-devel] [PATCH v3 02/16] i2c: have I2C receive operation return uint8_t List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: minyard@acm.org, qemu-devel@nongnu.org, "Dr . David Alan Gilbert" , Peter Maydell Cc: Paolo Bonzini , "Michael S . Tsirkin" , Corey Minyard Hi Corey, On 26/11/18 21:04, minyard@acm.org wrote: > From: Corey Minyard > > It is never supposed to fail and cannot return an error, so just > have it return the proper type. Have it return 0xff on nothing > available, since that's what would happen on a real bus. > > Signed-off-by: Corey Minyard > Reviewed-by: Peter Maydell > --- > hw/arm/pxa2xx.c | 2 +- > hw/arm/tosa.c | 4 ++-- > hw/arm/z2.c | 2 +- > hw/audio/wm8750.c | 2 +- > hw/display/sii9022.c | 2 +- > hw/display/ssd0303.c | 4 ++-- > hw/gpio/max7310.c | 2 +- > hw/i2c/core.c | 32 +++++++++++++------------------- > hw/i2c/i2c-ddc.c | 2 +- > hw/i2c/smbus_slave.c | 4 ++-- > hw/input/lm832x.c | 2 +- > hw/misc/pca9552.c | 2 +- > hw/misc/tmp105.c | 2 +- > hw/misc/tmp421.c | 2 +- > hw/nvram/eeprom_at24c.c | 4 ++-- > hw/timer/ds1338.c | 2 +- > hw/timer/m41t80.c | 2 +- > hw/timer/twl92230.c | 2 +- > include/hw/i2c/i2c.h | 7 +++---- > 19 files changed, 37 insertions(+), 44 deletions(-) > > diff --git a/hw/arm/pxa2xx.c b/hw/arm/pxa2xx.c > index f598a1c053..3d7c88910e 100644 > --- a/hw/arm/pxa2xx.c > +++ b/hw/arm/pxa2xx.c > @@ -1286,7 +1286,7 @@ static int pxa2xx_i2c_event(I2CSlave *i2c, enum i2c_event event) > return 0; > } > > -static int pxa2xx_i2c_rx(I2CSlave *i2c) > +static uint8_t pxa2xx_i2c_rx(I2CSlave *i2c) > { > PXA2xxI2CSlaveState *slave = PXA2XX_I2C_SLAVE(i2c); > PXA2xxI2CState *s = slave->host; > diff --git a/hw/arm/tosa.c b/hw/arm/tosa.c > index 7a925fa5e6..eef9d427e7 100644 > --- a/hw/arm/tosa.c > +++ b/hw/arm/tosa.c > @@ -197,10 +197,10 @@ static int tosa_dac_event(I2CSlave *i2c, enum i2c_event event) > return 0; > } > > -static int tosa_dac_recv(I2CSlave *s) > +static uint8_t tosa_dac_recv(I2CSlave *s) > { > printf("%s: recv not supported!!!\n", __func__); > - return -1; > + return 0xff; > } > > static void tosa_tg_init(PXA2xxState *cpu) > diff --git a/hw/arm/z2.c b/hw/arm/z2.c > index 697a822f1e..6f18d924df 100644 > --- a/hw/arm/z2.c > +++ b/hw/arm/z2.c > @@ -243,7 +243,7 @@ static int aer915_event(I2CSlave *i2c, enum i2c_event event) > return 0; > } > > -static int aer915_recv(I2CSlave *slave) > +static uint8_t aer915_recv(I2CSlave *slave) > { > AER915State *s = AER915(slave); > int retval = 0x00; > diff --git a/hw/audio/wm8750.c b/hw/audio/wm8750.c > index f4aa838f62..169b006ade 100644 > --- a/hw/audio/wm8750.c > +++ b/hw/audio/wm8750.c > @@ -561,7 +561,7 @@ static int wm8750_tx(I2CSlave *i2c, uint8_t data) > return 0; > } > > -static int wm8750_rx(I2CSlave *i2c) > +static uint8_t wm8750_rx(I2CSlave *i2c) > { > return 0x00; > } > diff --git a/hw/display/sii9022.c b/hw/display/sii9022.c > index eaf11a6e7b..9994385c35 100644 > --- a/hw/display/sii9022.c > +++ b/hw/display/sii9022.c > @@ -79,7 +79,7 @@ static int sii9022_event(I2CSlave *i2c, enum i2c_event event) > return 0; > } > > -static int sii9022_rx(I2CSlave *i2c) > +static uint8_t sii9022_rx(I2CSlave *i2c) > { > sii9022_state *s = SII9022(i2c); > uint8_t res = 0x00; > diff --git a/hw/display/ssd0303.c b/hw/display/ssd0303.c > index eb90ba26be..8edf34986c 100644 > --- a/hw/display/ssd0303.c > +++ b/hw/display/ssd0303.c > @@ -62,10 +62,10 @@ typedef struct { > uint8_t framebuffer[132*8]; > } ssd0303_state; > > -static int ssd0303_recv(I2CSlave *i2c) > +static uint8_t ssd0303_recv(I2CSlave *i2c) > { > BADF("Reads not implemented\n"); > - return -1; > + return 0xff; > } > > static int ssd0303_send(I2CSlave *i2c, uint8_t data) > diff --git a/hw/gpio/max7310.c b/hw/gpio/max7310.c > index a560e3afd2..f35a930276 100644 > --- a/hw/gpio/max7310.c > +++ b/hw/gpio/max7310.c > @@ -39,7 +39,7 @@ static void max7310_reset(DeviceState *dev) > s->command = 0x00; > } > > -static int max7310_rx(I2CSlave *i2c) > +static uint8_t max7310_rx(I2CSlave *i2c) > { > MAX7310State *s = MAX7310(i2c); > > diff --git a/hw/i2c/core.c b/hw/i2c/core.c > index b54725985a..15237ad073 100644 > --- a/hw/i2c/core.c > +++ b/hw/i2c/core.c > @@ -191,23 +191,17 @@ int i2c_send_recv(I2CBus *bus, uint8_t *data, bool send) i2c_send_recv() could benefit the same improvement. > } > return ret ? -1 : 0; > } else { > - if ((QLIST_EMPTY(&bus->current_devs)) || (bus->broadcast)) { > - return -1; > - } > - > - sc = I2C_SLAVE_GET_CLASS(QLIST_FIRST(&bus->current_devs)->elt); > - if (sc->recv) { > - s = QLIST_FIRST(&bus->current_devs)->elt; > - ret = sc->recv(s); > - trace_i2c_recv(s->address, ret); > - if (ret < 0) { > - return ret; > - } else { > - *data = ret; > - return 0; > + ret = 0xff; > + if (!QLIST_EMPTY(&bus->current_devs) && !bus->broadcast) { > + sc = I2C_SLAVE_GET_CLASS(QLIST_FIRST(&bus->current_devs)->elt); > + if (sc->recv) { > + s = QLIST_FIRST(&bus->current_devs)->elt; > + ret = sc->recv(s); > + trace_i2c_recv(s->address, ret); > } > } > - return -1; > + *data = ret; > + return 0; > } > } > > @@ -216,12 +210,12 @@ int i2c_send(I2CBus *bus, uint8_t data) > return i2c_send_recv(bus, &data, true); > } > > -int i2c_recv(I2CBus *bus) > +uint8_t i2c_recv(I2CBus *bus) > { > - uint8_t data; > - int ret = i2c_send_recv(bus, &data, false); > + uint8_t data = 0xff; > > - return ret < 0 ? ret : data; > + i2c_send_recv(bus, &data, false); > + return data; > } > > void i2c_nack(I2CBus *bus) > diff --git a/hw/i2c/i2c-ddc.c b/hw/i2c/i2c-ddc.c > index be34fe072c..95325358db 100644 > --- a/hw/i2c/i2c-ddc.c > +++ b/hw/i2c/i2c-ddc.c > @@ -51,7 +51,7 @@ static int i2c_ddc_event(I2CSlave *i2c, enum i2c_event event) > return 0; > } > > -static int i2c_ddc_rx(I2CSlave *i2c) > +static uint8_t i2c_ddc_rx(I2CSlave *i2c) > { > I2CDDCState *s = I2CDDC(i2c); > > diff --git a/hw/i2c/smbus_slave.c b/hw/i2c/smbus_slave.c > index 1e734752d7..549e7ae933 100644 > --- a/hw/i2c/smbus_slave.c > +++ b/hw/i2c/smbus_slave.c > @@ -156,11 +156,11 @@ static int smbus_i2c_event(I2CSlave *s, enum i2c_event event) > return 0; > } > > -static int smbus_i2c_recv(I2CSlave *s) > +static uint8_t smbus_i2c_recv(I2CSlave *s) > { > SMBusDevice *dev = SMBUS_DEVICE(s); > SMBusDeviceClass *sc = SMBUS_DEVICE_GET_CLASS(dev); > - int ret; > + uint8_t ret; > > switch (dev->mode) { > case SMBUS_RECV_BYTE: > diff --git a/hw/input/lm832x.c b/hw/input/lm832x.c > index 74da30d9ca..9ae037953d 100644 > --- a/hw/input/lm832x.c > +++ b/hw/input/lm832x.c > @@ -401,7 +401,7 @@ static int lm_i2c_event(I2CSlave *i2c, enum i2c_event event) > return 0; > } > > -static int lm_i2c_rx(I2CSlave *i2c) > +static uint8_t lm_i2c_rx(I2CSlave *i2c) > { > LM823KbdState *s = LM8323(i2c); > > diff --git a/hw/misc/pca9552.c b/hw/misc/pca9552.c > index 9775d5274a..7325d3f287 100644 > --- a/hw/misc/pca9552.c > +++ b/hw/misc/pca9552.c > @@ -115,7 +115,7 @@ static void pca9552_autoinc(PCA9552State *s) > } > } > > -static int pca9552_recv(I2CSlave *i2c) > +static uint8_t pca9552_recv(I2CSlave *i2c) > { > PCA9552State *s = PCA9552(i2c); > uint8_t ret; > diff --git a/hw/misc/tmp105.c b/hw/misc/tmp105.c > index 0918f3a6ea..a4cae665b7 100644 > --- a/hw/misc/tmp105.c > +++ b/hw/misc/tmp105.c > @@ -147,7 +147,7 @@ static void tmp105_write(TMP105State *s) > } > } > > -static int tmp105_rx(I2CSlave *i2c) > +static uint8_t tmp105_rx(I2CSlave *i2c) > { > TMP105State *s = TMP105(i2c); > > diff --git a/hw/misc/tmp421.c b/hw/misc/tmp421.c > index c234044305..a75eb994a8 100644 > --- a/hw/misc/tmp421.c > +++ b/hw/misc/tmp421.c > @@ -249,7 +249,7 @@ static void tmp421_write(TMP421State *s) > } > } > > -static int tmp421_rx(I2CSlave *i2c) > +static uint8_t tmp421_rx(I2CSlave *i2c) > { > TMP421State *s = TMP421(i2c); > > diff --git a/hw/nvram/eeprom_at24c.c b/hw/nvram/eeprom_at24c.c > index 27cd01e615..d1456dafbd 100644 > --- a/hw/nvram/eeprom_at24c.c > +++ b/hw/nvram/eeprom_at24c.c > @@ -74,10 +74,10 @@ int at24c_eeprom_event(I2CSlave *s, enum i2c_event event) > } > > static > -int at24c_eeprom_recv(I2CSlave *s) > +uint8_t at24c_eeprom_recv(I2CSlave *s) > { > EEPROMState *ee = AT24C_EE(s); > - int ret; > + uint8_t ret; > > ret = ee->mem[ee->cur]; > > diff --git a/hw/timer/ds1338.c b/hw/timer/ds1338.c > index 3849b74a68..03da75486b 100644 > --- a/hw/timer/ds1338.c > +++ b/hw/timer/ds1338.c > @@ -117,7 +117,7 @@ static int ds1338_event(I2CSlave *i2c, enum i2c_event event) > return 0; > } > > -static int ds1338_recv(I2CSlave *i2c) > +static uint8_t ds1338_recv(I2CSlave *i2c) > { > DS1338State *s = DS1338(i2c); > uint8_t res; > diff --git a/hw/timer/m41t80.c b/hw/timer/m41t80.c > index 734d7d95fc..c45b9297d8 100644 > --- a/hw/timer/m41t80.c > +++ b/hw/timer/m41t80.c > @@ -40,7 +40,7 @@ static int m41t80_send(I2CSlave *i2c, uint8_t data) > return 0; > } > > -static int m41t80_recv(I2CSlave *i2c) > +static uint8_t m41t80_recv(I2CSlave *i2c) > { > M41t80State *s = M41T80(i2c); > struct tm now; > diff --git a/hw/timer/twl92230.c b/hw/timer/twl92230.c > index 3b43b46199..659b216dca 100644 > --- a/hw/timer/twl92230.c > +++ b/hw/timer/twl92230.c > @@ -737,7 +737,7 @@ static int menelaus_tx(I2CSlave *i2c, uint8_t data) > return 0; > } > > -static int menelaus_rx(I2CSlave *i2c) > +static uint8_t menelaus_rx(I2CSlave *i2c) > { > MenelausState *s = TWL92230(i2c); > > diff --git a/include/hw/i2c/i2c.h b/include/hw/i2c/i2c.h > index 5dc166158b..75c5bd638b 100644 > --- a/include/hw/i2c/i2c.h > +++ b/include/hw/i2c/i2c.h > @@ -33,10 +33,9 @@ typedef struct I2CSlaveClass { > > /* > * Slave to master. This cannot fail, the device should always > - * return something here. Negative values probably result in 0xff > - * and a possible log from the driver, and shouldn't be used. > + * return something here. Maybe use simple comment as "Master receives the data sent by the Slave" > */ > - int (*recv)(I2CSlave *s); > + uint8_t (*recv)(I2CSlave *s); > > /* > * Notify the slave of a bus state change. For start event, > @@ -78,7 +77,7 @@ void i2c_end_transfer(I2CBus *bus); > void i2c_nack(I2CBus *bus); > int i2c_send_recv(I2CBus *bus, uint8_t *data, bool send); > int i2c_send(I2CBus *bus, uint8_t data); > -int i2c_recv(I2CBus *bus); > +uint8_t i2c_recv(I2CBus *bus); > > DeviceState *i2c_create_slave(I2CBus *bus, const char *name, uint8_t addr); > Reviewed-by: Philippe Mathieu-Daudé Tested-by: Philippe Mathieu-Daudé