mmc: use empty initializer list to zero-clear structures

In the MMC subsystem, we see such initializers that only clears the
first member explicitly.

For example,

  struct mmc_request mrq = {NULL};

sets the first member (.sbc) to NULL explicitly.  However, this is
an unstable form because we may insert a non-pointer member at the
top of the struct mmc_request in the future. (if we do so, the
compiler will spit warnings.)

So, using a designated initializer is preferred coding style.  The
expression above is equivalent to:

  struct mmc_request mrq = { .sbc = NULL };

Of course, this does not express our intention.  We want to fill
all struct members with zeros.  Please note struct members are
implicitly zero-cleared unless otherwise specified in the initializer.

After all, the most reasonable (and stable) form is:

  struct mmc_request mrq = {};

Do likewise for mmc_command, mmc_data as well.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/mmc/core/block.c

@@ -442,9 +442,9 @@ static int ioctl_do_sanitize(struct mmc_card *card)
 static int __mmc_blk_ioctl_cmd(struct mmc_card *card, struct mmc_blk_data *md,
 			       struct mmc_blk_ioc_data *idata)
 {
-	struct mmc_command cmd = {0};
-	struct mmc_data data = {0};
-	struct mmc_request mrq = {NULL};
+	struct mmc_command cmd = {};
+	struct mmc_data data = {};
+	struct mmc_request mrq = {};
 	struct scatterlist sg;
 	int err;
 	int is_rpmb = false;
@@ -768,9 +768,9 @@ static u32 mmc_sd_num_wr_blocks(struct mmc_card *card)
 	u32 result;
 	__be32 *blocks;
 
-	struct mmc_request mrq = {NULL};
-	struct mmc_command cmd = {0};
-	struct mmc_data data = {0};
+	struct mmc_request mrq = {};
+	struct mmc_command cmd = {};
+	struct mmc_data data = {};
 
 	struct scatterlist sg;
 
@@ -819,7 +819,7 @@ static u32 mmc_sd_num_wr_blocks(struct mmc_card *card)
 
 static int get_card_status(struct mmc_card *card, u32 *status, int retries)
 {
-	struct mmc_command cmd = {0};
+	struct mmc_command cmd = {};
 	int err;
 
 	cmd.opcode = MMC_SEND_STATUS;
@@ -884,7 +884,7 @@ static int send_stop(struct mmc_card *card, unsigned int timeout_ms,
 		struct request *req, bool *gen_err, u32 *stop_status)
 {
 	struct mmc_host *host = card->host;
-	struct mmc_command cmd = {0};
+	struct mmc_command cmd = {};
 	int err;
 	bool use_r1b_resp = rq_data_dir(req) == WRITE;
 

drivers/mmc/core/core.c

@@ -807,7 +807,7 @@ EXPORT_SYMBOL(mmc_interrupt_hpi);
  */
 int mmc_wait_for_cmd(struct mmc_host *host, struct mmc_command *cmd, int retries)
 {
-	struct mmc_request mrq = {NULL};
+	struct mmc_request mrq = {};
 
 	WARN_ON(!host->claimed);
 
@@ -1648,7 +1648,7 @@ int __mmc_set_signal_voltage(struct mmc_host *host, int signal_voltage)
 
 int mmc_set_signal_voltage(struct mmc_host *host, int signal_voltage, u32 ocr)
 {
-	struct mmc_command cmd = {0};
+	struct mmc_command cmd = {};
 	int err = 0;
 	u32 clock;
 
@@ -2129,7 +2129,7 @@ static unsigned int mmc_erase_timeout(struct mmc_card *card,
 static int mmc_do_erase(struct mmc_card *card, unsigned int from,
 			unsigned int to, unsigned int arg)
 {
-	struct mmc_command cmd = {0};
+	struct mmc_command cmd = {};
 	unsigned int qty = 0, busy_timeout = 0;
 	bool use_r1b_resp = false;
 	unsigned long timeout;
@@ -2551,7 +2551,7 @@ EXPORT_SYMBOL(mmc_calc_max_discard);
 
 int mmc_set_blocklen(struct mmc_card *card, unsigned int blocklen)
 {
-	struct mmc_command cmd = {0};
+	struct mmc_command cmd = {};
 
 	if (mmc_card_blockaddr(card) || mmc_card_ddr52(card) ||
 	    mmc_card_hs400(card) || mmc_card_hs400es(card))
@@ -2567,7 +2567,7 @@ EXPORT_SYMBOL(mmc_set_blocklen);
 int mmc_set_blockcount(struct mmc_card *card, unsigned int blockcount,
 			bool is_rel_write)
 {
-	struct mmc_command cmd = {0};
+	struct mmc_command cmd = {};
 
 	cmd.opcode = MMC_SET_BLOCK_COUNT;
 	cmd.arg = blockcount & 0x0000FFFF;

drivers/mmc/core/mmc.c

@@ -1817,7 +1817,7 @@ static int mmc_can_sleep(struct mmc_card *card)
 
 static int mmc_sleep(struct mmc_host *host)
 {
-	struct mmc_command cmd = {0};
+	struct mmc_command cmd = {};
 	struct mmc_card *card = host->card;
 	unsigned int timeout_ms = DIV_ROUND_UP(card->ext_csd.sa_timeout, 10000);
 	int err;

drivers/mmc/core/mmc_ops.c

@@ -57,7 +57,7 @@ static const u8 tuning_blk_pattern_8bit[] = {
 int mmc_send_status(struct mmc_card *card, u32 *status)
 {
 	int err;
-	struct mmc_command cmd = {0};
+	struct mmc_command cmd = {};
 
 	cmd.opcode = MMC_SEND_STATUS;
 	if (!mmc_host_is_spi(card->host))
@@ -79,7 +79,7 @@ int mmc_send_status(struct mmc_card *card, u32 *status)
 
 static int _mmc_select_card(struct mmc_host *host, struct mmc_card *card)
 {
-	struct mmc_command cmd = {0};
+	struct mmc_command cmd = {};
 
 	cmd.opcode = MMC_SELECT_CARD;
 
@@ -115,7 +115,7 @@ int mmc_deselect_cards(struct mmc_host *host)
  */
 int mmc_set_dsr(struct mmc_host *host)
 {
-	struct mmc_command cmd = {0};
+	struct mmc_command cmd = {};
 
 	cmd.opcode = MMC_SET_DSR;
 
@@ -128,7 +128,7 @@ int mmc_set_dsr(struct mmc_host *host)
 int mmc_go_idle(struct mmc_host *host)
 {
 	int err;
-	struct mmc_command cmd = {0};
+	struct mmc_command cmd = {};
 
 	/*
 	 * Non-SPI hosts need to prevent chipselect going active during
@@ -164,7 +164,7 @@ int mmc_go_idle(struct mmc_host *host)
 
 int mmc_send_op_cond(struct mmc_host *host, u32 ocr, u32 *rocr)
 {
-	struct mmc_command cmd = {0};
+	struct mmc_command cmd = {};
 	int i, err = 0;
 
 	cmd.opcode = MMC_SEND_OP_COND;
@@ -203,7 +203,7 @@ int mmc_send_op_cond(struct mmc_host *host, u32 ocr, u32 *rocr)
 int mmc_all_send_cid(struct mmc_host *host, u32 *cid)
 {
 	int err;
-	struct mmc_command cmd = {0};
+	struct mmc_command cmd = {};
 
 	cmd.opcode = MMC_ALL_SEND_CID;
 	cmd.arg = 0;
@@ -220,7 +220,7 @@ int mmc_all_send_cid(struct mmc_host *host, u32 *cid)
 
 int mmc_set_relative_addr(struct mmc_card *card)
 {
-	struct mmc_command cmd = {0};
+	struct mmc_command cmd = {};
 
 	cmd.opcode = MMC_SET_RELATIVE_ADDR;
 	cmd.arg = card->rca << 16;
@@ -233,7 +233,7 @@ static int
 mmc_send_cxd_native(struct mmc_host *host, u32 arg, u32 *cxd, int opcode)
 {
 	int err;
-	struct mmc_command cmd = {0};
+	struct mmc_command cmd = {};
 
 	cmd.opcode = opcode;
 	cmd.arg = arg;
@@ -256,9 +256,9 @@ static int
 mmc_send_cxd_data(struct mmc_card *card, struct mmc_host *host,
 		u32 opcode, void *buf, unsigned len)
 {
-	struct mmc_request mrq = {NULL};
-	struct mmc_command cmd = {0};
-	struct mmc_data data = {0};
+	struct mmc_request mrq = {};
+	struct mmc_command cmd = {};
+	struct mmc_data data = {};
 	struct scatterlist sg;
 
 	mrq.cmd = &cmd;
@@ -387,7 +387,7 @@ EXPORT_SYMBOL_GPL(mmc_get_ext_csd);
 
 int mmc_spi_read_ocr(struct mmc_host *host, int highcap, u32 *ocrp)
 {
-	struct mmc_command cmd = {0};
+	struct mmc_command cmd = {};
 	int err;
 
 	cmd.opcode = MMC_SPI_READ_OCR;
@@ -402,7 +402,7 @@ int mmc_spi_read_ocr(struct mmc_host *host, int highcap, u32 *ocrp)
 
 int mmc_spi_set_crc(struct mmc_host *host, int use_crc)
 {
-	struct mmc_command cmd = {0};
+	struct mmc_command cmd = {};
 	int err;
 
 	cmd.opcode = MMC_SPI_CRC_ON_OFF;
@@ -530,7 +530,7 @@ int __mmc_switch(struct mmc_card *card, u8 set, u8 index, u8 value,
 {
 	struct mmc_host *host = card->host;
 	int err;
-	struct mmc_command cmd = {0};
+	struct mmc_command cmd = {};
 	bool use_r1b_resp = use_busy_signal;
 	unsigned char old_timing = host->ios.timing;
 
@@ -610,9 +610,9 @@ EXPORT_SYMBOL_GPL(mmc_switch);
 
 int mmc_send_tuning(struct mmc_host *host, u32 opcode, int *cmd_error)
 {
-	struct mmc_request mrq = {NULL};
-	struct mmc_command cmd = {0};
-	struct mmc_data data = {0};
+	struct mmc_request mrq = {};
+	struct mmc_command cmd = {};
+	struct mmc_data data = {};
 	struct scatterlist sg;
 	struct mmc_ios *ios = &host->ios;
 	const u8 *tuning_block_pattern;
@@ -679,7 +679,7 @@ EXPORT_SYMBOL_GPL(mmc_send_tuning);
 
 int mmc_abort_tuning(struct mmc_host *host, u32 opcode)
 {
-	struct mmc_command cmd = {0};
+	struct mmc_command cmd = {};
 
 	/*
 	 * eMMC specification specifies that CMD12 can be used to stop a tuning
@@ -706,9 +706,9 @@ static int
 mmc_send_bus_test(struct mmc_card *card, struct mmc_host *host, u8 opcode,
 		  u8 len)
 {
-	struct mmc_request mrq = {NULL};
-	struct mmc_command cmd = {0};
-	struct mmc_data data = {0};
+	struct mmc_request mrq = {};
+	struct mmc_command cmd = {};
+	struct mmc_data data = {};
 	struct scatterlist sg;
 	u8 *data_buf;
 	u8 *test_buf;
@@ -802,7 +802,7 @@ int mmc_bus_test(struct mmc_card *card, u8 bus_width)
 
 int mmc_send_hpi_cmd(struct mmc_card *card, u32 *status)
 {
-	struct mmc_command cmd = {0};
+	struct mmc_command cmd = {};
 	unsigned int opcode;
 	int err;
 

drivers/mmc/core/mmc_test.c

@@ -260,7 +260,7 @@ static int mmc_test_busy(struct mmc_command *cmd)
 static int mmc_test_wait_busy(struct mmc_test_card *test)
 {
 	int ret, busy;
-	struct mmc_command cmd = {0};
+	struct mmc_command cmd = {};
 
 	busy = 0;
 	do {
@@ -292,10 +292,10 @@ static int mmc_test_wait_busy(struct mmc_test_card *test)
 static int mmc_test_buffer_transfer(struct mmc_test_card *test,
 	u8 *buffer, unsigned addr, unsigned blksz, int write)
 {
-	struct mmc_request mrq = {0};
-	struct mmc_command cmd = {0};
-	struct mmc_command stop = {0};
-	struct mmc_data data = {0};
+	struct mmc_request mrq = {};
+	struct mmc_command cmd = {};
+	struct mmc_command stop = {};
+	struct mmc_data data = {};
 
 	struct scatterlist sg;
 
@@ -885,10 +885,10 @@ static int mmc_test_simple_transfer(struct mmc_test_card *test,
 	struct scatterlist *sg, unsigned sg_len, unsigned dev_addr,
 	unsigned blocks, unsigned blksz, int write)
 {
-	struct mmc_request mrq = {0};
-	struct mmc_command cmd = {0};
-	struct mmc_command stop = {0};
-	struct mmc_data data = {0};
+	struct mmc_request mrq = {};
+	struct mmc_command cmd = {};
+	struct mmc_command stop = {};
+	struct mmc_data data = {};
 
 	mrq.cmd = &cmd;
 	mrq.data = &data;
@@ -910,10 +910,10 @@ static int mmc_test_simple_transfer(struct mmc_test_card *test,
 static int mmc_test_broken_transfer(struct mmc_test_card *test,
 	unsigned blocks, unsigned blksz, int write)
 {
-	struct mmc_request mrq = {0};
-	struct mmc_command cmd = {0};
-	struct mmc_command stop = {0};
-	struct mmc_data data = {0};
+	struct mmc_request mrq = {};
+	struct mmc_command cmd = {};
+	struct mmc_command stop = {};
+	struct mmc_data data = {};
 
 	struct scatterlist sg;
 

drivers/mmc/core/sd_ops.c

@@ -25,7 +25,7 @@
 int mmc_app_cmd(struct mmc_host *host, struct mmc_card *card)
 {
 	int err;
-	struct mmc_command cmd = {0};
+	struct mmc_command cmd = {};
 
 	if (WARN_ON(card && card->host != host))
 		return -EINVAL;
@@ -68,7 +68,7 @@ EXPORT_SYMBOL_GPL(mmc_app_cmd);
 int mmc_wait_for_app_cmd(struct mmc_host *host, struct mmc_card *card,
 	struct mmc_command *cmd, int retries)
 {
-	struct mmc_request mrq = {NULL};
+	struct mmc_request mrq = {};
 
 	int i, err;
 
@@ -120,7 +120,7 @@ EXPORT_SYMBOL(mmc_wait_for_app_cmd);
 
 int mmc_app_set_bus_width(struct mmc_card *card, int width)
 {
-	struct mmc_command cmd = {0};
+	struct mmc_command cmd = {};
 
 	cmd.opcode = SD_APP_SET_BUS_WIDTH;
 	cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
@@ -141,7 +141,7 @@ int mmc_app_set_bus_width(struct mmc_card *card, int width)
 
 int mmc_send_app_op_cond(struct mmc_host *host, u32 ocr, u32 *rocr)
 {
-	struct mmc_command cmd = {0};
+	struct mmc_command cmd = {};
 	int i, err = 0;
 
 	cmd.opcode = SD_APP_OP_COND;
@@ -185,7 +185,7 @@ int mmc_send_app_op_cond(struct mmc_host *host, u32 ocr, u32 *rocr)
 
 int mmc_send_if_cond(struct mmc_host *host, u32 ocr)
 {
-	struct mmc_command cmd = {0};
+	struct mmc_command cmd = {};
 	int err;
 	static const u8 test_pattern = 0xAA;
 	u8 result_pattern;
@@ -217,7 +217,7 @@ int mmc_send_if_cond(struct mmc_host *host, u32 ocr)
 int mmc_send_relative_addr(struct mmc_host *host, unsigned int *rca)
 {
 	int err;
-	struct mmc_command cmd = {0};
+	struct mmc_command cmd = {};
 
 	cmd.opcode = SD_SEND_RELATIVE_ADDR;
 	cmd.arg = 0;
@@ -235,9 +235,9 @@ int mmc_send_relative_addr(struct mmc_host *host, unsigned int *rca)
 int mmc_app_send_scr(struct mmc_card *card, u32 *scr)
 {
 	int err;
-	struct mmc_request mrq = {NULL};
-	struct mmc_command cmd = {0};
-	struct mmc_data data = {0};
+	struct mmc_request mrq = {};
+	struct mmc_command cmd = {};
+	struct mmc_data data = {};
 	struct scatterlist sg;
 	void *data_buf;
 
@@ -290,9 +290,9 @@ int mmc_app_send_scr(struct mmc_card *card, u32 *scr)
 int mmc_sd_switch(struct mmc_card *card, int mode, int group,
 	u8 value, u8 *resp)
 {
-	struct mmc_request mrq = {NULL};
-	struct mmc_command cmd = {0};
-	struct mmc_data data = {0};
+	struct mmc_request mrq = {};
+	struct mmc_command cmd = {};
+	struct mmc_data data = {};
 	struct scatterlist sg;
 
 	/* NOTE: caller guarantees resp is heap-allocated */
@@ -332,9 +332,9 @@ int mmc_sd_switch(struct mmc_card *card, int mode, int group,
 int mmc_app_sd_status(struct mmc_card *card, void *ssr)
 {
 	int err;
-	struct mmc_request mrq = {NULL};
-	struct mmc_command cmd = {0};
-	struct mmc_data data = {0};
+	struct mmc_request mrq = {};
+	struct mmc_command cmd = {};
+	struct mmc_data data = {};
 	struct scatterlist sg;
 
 	/* NOTE: caller guarantees ssr is heap-allocated */

drivers/mmc/core/sdio_ops.c

@@ -21,7 +21,7 @@
 
 int mmc_send_io_op_cond(struct mmc_host *host, u32 ocr, u32 *rocr)
 {
-	struct mmc_command cmd = {0};
+	struct mmc_command cmd = {};
 	int i, err = 0;
 
 	cmd.opcode = SD_IO_SEND_OP_COND;
@@ -66,7 +66,7 @@ int mmc_send_io_op_cond(struct mmc_host *host, u32 ocr, u32 *rocr)
 static int mmc_io_rw_direct_host(struct mmc_host *host, int write, unsigned fn,
 	unsigned addr, u8 in, u8 *out)
 {
-	struct mmc_command cmd = {0};
+	struct mmc_command cmd = {};
 	int err;
 
 	if (fn > 7)
@@ -118,9 +118,9 @@ int mmc_io_rw_direct(struct mmc_card *card, int write, unsigned fn,
 int mmc_io_rw_extended(struct mmc_card *card, int write, unsigned fn,
 	unsigned addr, int incr_addr, u8 *buf, unsigned blocks, unsigned blksz)
 {
-	struct mmc_request mrq = {NULL};
-	struct mmc_command cmd = {0};
-	struct mmc_data data = {0};
+	struct mmc_request mrq = {};
+	struct mmc_command cmd = {};
+	struct mmc_data data = {};
 	struct scatterlist sg, *sg_ptr;
 	struct sg_table sgtable;
 	unsigned int nents, left_size, i;

drivers/mmc/host/rtsx_pci_sdmmc.c

@@ -707,7 +707,7 @@ static int sd_tuning_rx_cmd(struct realtek_pci_sdmmc *host,
 		u8 opcode, u8 sample_point)
 {
 	int err;
-	struct mmc_command cmd = {0};
+	struct mmc_command cmd = {};
 
 	err = sd_change_phase(host, sample_point, true);
 	if (err < 0)

drivers/mmc/host/rtsx_usb_sdmmc.c

@@ -682,7 +682,7 @@ static int sd_tuning_rx_cmd(struct rtsx_usb_sdmmc *host,
 		u8 opcode, u8 sample_point)
 {
 	int err;
-	struct mmc_command cmd = {0};
+	struct mmc_command cmd = {};
 
 	err = sd_change_phase(host, sample_point, 0);
 	if (err)

drivers/mmc/host/sdhci.c

@@ -2021,8 +2021,8 @@ static void sdhci_send_tuning(struct sdhci_host *host, u32 opcode,
 			      unsigned long flags)
 {
 	struct mmc_host *mmc = host->mmc;
-	struct mmc_command cmd = {0};
-	struct mmc_request mrq = {NULL};
+	struct mmc_command cmd = {};
+	struct mmc_request mrq = {};
 
 	cmd.opcode = opcode;
 	cmd.flags = MMC_RSP_R1 | MMC_CMD_ADTC;