From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Subject: [PATCH] tpm: constify transmit data pointers Date: Thu, 7 Sep 2017 15:30:45 +0200 Message-ID: <20170907133130.2463746-1-arnd@arndb.de> Return-path: Sender: linux-kernel-owner@vger.kernel.org To: Peter Huewe , Marcel Selhorst , Jarkko Sakkinen Cc: Arnd Bergmann , Jason Gunthorpe , Colin Ian King , tpmdd-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org List-Id: tpmdd-devel@lists.sourceforge.net Making cmd_getticks 'const' introduced a couple of harmless warnings: drivers/char/tpm/tpm_tis_core.c: In function 'probe_itpm': drivers/char/tpm/tpm_tis_core.c:469:31: error: passing argument 2 of 'tpm_tis_send_data' discards 'const' qualifier from pointer target type [-Werror=discarded-qualifiers] rc = tpm_tis_send_data(chip, cmd_getticks, len); drivers/char/tpm/tpm_tis_core.c:477:31: error: passing argument 2 of 'tpm_tis_send_data' discards 'const' qualifier from pointer target type [-Werror=discarded-qualifiers] rc = tpm_tis_send_data(chip, cmd_getticks, len); drivers/char/tpm/tpm_tis_core.c:255:12: note: expected 'u8 * {aka unsigned char *}' but argument is of type 'const u8 * {aka const unsigned char *}' static int tpm_tis_send_data(struct tpm_chip *chip, u8 *buf, size_t len) This changes the related functions to all take 'const' pointers so that gcc can see this as being correct. I had to slightly modify the logic around tpm_tis_spi_transfer() for this to work without introducing ugly casts. Fixes: 5e35bd8e06b9 ("tpm_tis: make array cmd_getticks static const to shink object code size") Signed-off-by: Arnd Bergmann --- drivers/char/tpm/tpm_tis.c | 2 +- drivers/char/tpm/tpm_tis_core.c | 4 ++-- drivers/char/tpm/tpm_tis_core.h | 4 ++-- drivers/char/tpm/tpm_tis_spi.c | 25 +++++++++++-------------- 4 files changed, 16 insertions(+), 19 deletions(-) diff --git a/drivers/char/tpm/tpm_tis.c b/drivers/char/tpm/tpm_tis.c index 7e55aa9ce680..ebd0e75a3e4d 100644 --- a/drivers/char/tpm/tpm_tis.c +++ b/drivers/char/tpm/tpm_tis.c @@ -223,7 +223,7 @@ static int tpm_tcg_read_bytes(struct tpm_tis_data *data, u32 addr, u16 len, } static int tpm_tcg_write_bytes(struct tpm_tis_data *data, u32 addr, u16 len, - u8 *value) + const u8 *value) { struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data); diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c index 1e957e923d21..fdde971bc810 100644 --- a/drivers/char/tpm/tpm_tis_core.c +++ b/drivers/char/tpm/tpm_tis_core.c @@ -252,7 +252,7 @@ static int tpm_tis_recv(struct tpm_chip *chip, u8 *buf, size_t count) * tpm.c can skip polling for the data to be available as the interrupt is * waited for here */ -static int tpm_tis_send_data(struct tpm_chip *chip, u8 *buf, size_t len) +static int tpm_tis_send_data(struct tpm_chip *chip, const u8 *buf, size_t len) { struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev); int rc, status, burstcnt; @@ -343,7 +343,7 @@ static void disable_interrupts(struct tpm_chip *chip) * tpm.c can skip polling for the data to be available as the interrupt is * waited for here */ -static int tpm_tis_send_main(struct tpm_chip *chip, u8 *buf, size_t len) +static int tpm_tis_send_main(struct tpm_chip *chip, const u8 *buf, size_t len) { struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev); int rc; diff --git a/drivers/char/tpm/tpm_tis_core.h b/drivers/char/tpm/tpm_tis_core.h index e2212f021a02..6bbac319ff3b 100644 --- a/drivers/char/tpm/tpm_tis_core.h +++ b/drivers/char/tpm/tpm_tis_core.h @@ -98,7 +98,7 @@ struct tpm_tis_phy_ops { int (*read_bytes)(struct tpm_tis_data *data, u32 addr, u16 len, u8 *result); int (*write_bytes)(struct tpm_tis_data *data, u32 addr, u16 len, - u8 *value); + const u8 *value); int (*read16)(struct tpm_tis_data *data, u32 addr, u16 *result); int (*read32)(struct tpm_tis_data *data, u32 addr, u32 *result); int (*write32)(struct tpm_tis_data *data, u32 addr, u32 src); @@ -128,7 +128,7 @@ static inline int tpm_tis_read32(struct tpm_tis_data *data, u32 addr, } static inline int tpm_tis_write_bytes(struct tpm_tis_data *data, u32 addr, - u16 len, u8 *value) + u16 len, const u8 *value) { return data->phy_ops->write_bytes(data, addr, len, value); } diff --git a/drivers/char/tpm/tpm_tis_spi.c b/drivers/char/tpm/tpm_tis_spi.c index 88fe72ae967f..e49f5b9b739a 100644 --- a/drivers/char/tpm/tpm_tis_spi.c +++ b/drivers/char/tpm/tpm_tis_spi.c @@ -57,7 +57,7 @@ static inline struct tpm_tis_spi_phy *to_tpm_tis_spi_phy(struct tpm_tis_data *da } static int tpm_tis_spi_transfer(struct tpm_tis_data *data, u32 addr, u16 len, - u8 *buffer, u8 direction) + u8 *in, const u8 *out) { struct tpm_tis_spi_phy *phy = to_tpm_tis_spi_phy(data); int ret = 0; @@ -71,7 +71,7 @@ static int tpm_tis_spi_transfer(struct tpm_tis_data *data, u32 addr, u16 len, while (len) { transfer_len = min_t(u16, len, MAX_SPI_FRAMESIZE); - phy->tx_buf[0] = direction | (transfer_len - 1); + phy->tx_buf[0] = (in ? 0x80 : 0) | (transfer_len - 1); phy->tx_buf[1] = 0xd4; phy->tx_buf[2] = addr >> 8; phy->tx_buf[3] = addr; @@ -112,14 +112,8 @@ static int tpm_tis_spi_transfer(struct tpm_tis_data *data, u32 addr, u16 len, spi_xfer.cs_change = 0; spi_xfer.len = transfer_len; spi_xfer.delay_usecs = 5; - - if (direction) { - spi_xfer.tx_buf = NULL; - spi_xfer.rx_buf = buffer; - } else { - spi_xfer.tx_buf = buffer; - spi_xfer.rx_buf = NULL; - } + spi_xfer.tx_buf = out; + spi_xfer.rx_buf = in; spi_message_init(&m); spi_message_add_tail(&spi_xfer, &m); @@ -128,7 +122,10 @@ static int tpm_tis_spi_transfer(struct tpm_tis_data *data, u32 addr, u16 len, goto exit; len -= transfer_len; - buffer += transfer_len; + if (in) + in += transfer_len; + if (out) + out += transfer_len; } exit: @@ -139,13 +136,13 @@ static int tpm_tis_spi_transfer(struct tpm_tis_data *data, u32 addr, u16 len, static int tpm_tis_spi_read_bytes(struct tpm_tis_data *data, u32 addr, u16 len, u8 *result) { - return tpm_tis_spi_transfer(data, addr, len, result, 0x80); + return tpm_tis_spi_transfer(data, addr, len, result, NULL); } static int tpm_tis_spi_write_bytes(struct tpm_tis_data *data, u32 addr, - u16 len, u8 *value) + u16 len, const u8 *value) { - return tpm_tis_spi_transfer(data, addr, len, value, 0); + return tpm_tis_spi_transfer(data, addr, len, NULL, value); } static int tpm_tis_spi_read16(struct tpm_tis_data *data, u32 addr, u16 *result) -- 2.9.0