mmc: mediatek: Drop pointer to mmc_host from msdc_host

The MediaTek MMC driver uses  pointer to get from private
msdc_host structure to the generic mmc_host structure.
However mmc_host always precedes msdc_host in memory so compute
its address with a subtraction (which is cheaper than a dereference)
using mmc_from_priv() and drop the extra pointer.
Signed-off-by: Amey Narkhede <ameynarkhede03@gmail.com>
Link: https://lore.kernel.org/r/20200917192624.548720-1-ameynarkhede03@gmail.comSigned-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/mmc/host/mtk-sd.c

@@ -397,7 +397,6 @@ struct msdc_delay_phase {
 struct msdc_host {
 	struct device *dev;
 	const struct mtk_mmc_compatible *dev_comp;
-	struct mmc_host *mmc;	/* mmc structure */
 	int cmd_rsp;
 
 	spinlock_t lock;
@@ -734,14 +733,15 @@ static void msdc_unprepare_data(struct msdc_host *host, struct mmc_request *mrq)
 
 static u64 msdc_timeout_cal(struct msdc_host *host, u64 ns, u64 clks)
 {
+	struct mmc_host *mmc = mmc_from_priv(host);
 	u64 timeout, clk_ns;
 	u32 mode = 0;
 
-	if (host->mmc->actual_clock == 0) {
+	if (mmc->actual_clock == 0) {
 		timeout = 0;
 	} else {
 		clk_ns  = 1000000000ULL;
-		do_div(clk_ns, host->mmc->actual_clock);
+		do_div(clk_ns, mmc->actual_clock);
 		timeout = ns + clk_ns - 1;
 		do_div(timeout, clk_ns);
 		timeout += clks;
@@ -802,6 +802,7 @@ static void msdc_ungate_clock(struct msdc_host *host)
 
 static void msdc_set_mclk(struct msdc_host *host, unsigned char timing, u32 hz)
 {
+	struct mmc_host *mmc = mmc_from_priv(host);
 	u32 mode;
 	u32 flags;
 	u32 div;
@@ -811,7 +812,7 @@ static void msdc_set_mclk(struct msdc_host *host, unsigned char timing, u32 hz)
 	if (!hz) {
 		dev_dbg(host->dev, "set mclk to 0\n");
 		host->mclk = 0;
-		host->mmc->actual_clock = 0;
+		mmc->actual_clock = 0;
 		sdr_clr_bits(host->base + MSDC_CFG, MSDC_CFG_CKPDN);
 		return;
 	}
@@ -890,7 +891,7 @@ static void msdc_set_mclk(struct msdc_host *host, unsigned char timing, u32 hz)
 	while (!(readl(host->base + MSDC_CFG) & MSDC_CFG_CKSTB))
 		cpu_relax();
 	sdr_set_bits(host->base + MSDC_CFG, MSDC_CFG_CKPDN);
-	host->mmc->actual_clock = sclk;
+	mmc->actual_clock = sclk;
 	host->mclk = hz;
 	host->timing = timing;
 	/* need because clk changed. */
@@ -901,7 +902,7 @@ static void msdc_set_mclk(struct msdc_host *host, unsigned char timing, u32 hz)
 	 * mmc_select_hs400() will drop to 50Mhz and High speed mode,
 	 * tune result of hs200/200Mhz is not suitable for 50Mhz
 	 */
-	if (host->mmc->actual_clock <= 52000000) {
+	if (mmc->actual_clock <= 52000000) {
 		writel(host->def_tune_para.iocon, host->base + MSDC_IOCON);
 		if (host->top_base) {
 			writel(host->def_tune_para.emmc_top_control,
@@ -932,7 +933,7 @@ static void msdc_set_mclk(struct msdc_host *host, unsigned char timing, u32 hz)
 		sdr_set_field(host->base + tune_reg,
 			      MSDC_PAD_TUNE_CMDRRDLY,
 			      host->hs400_cmd_int_delay);
-	dev_dbg(host->dev, "sclk: %d, timing: %d\n", host->mmc->actual_clock,
+	dev_dbg(host->dev, "sclk: %d, timing: %d\n", mmc->actual_clock,
 		timing);
 }
 
@@ -967,6 +968,7 @@ static inline u32 msdc_cmd_find_resp(struct msdc_host *host,
 static inline u32 msdc_cmd_prepare_raw_cmd(struct msdc_host *host,
 		struct mmc_request *mrq, struct mmc_command *cmd)
 {
+	struct mmc_host *mmc = mmc_from_priv(host);
 	/* rawcmd :
 	 * vol_swt << 30 | auto_cmd << 28 | blklen << 16 | go_irq << 15 |
 	 * stop << 14 | rw << 13 | dtype << 11 | rsptyp << 7 | brk << 6 | opcode
@@ -993,7 +995,7 @@ static inline u32 msdc_cmd_prepare_raw_cmd(struct msdc_host *host,
 		struct mmc_data *data = cmd->data;
 
 		if (mmc_op_multi(opcode)) {
-			if (mmc_card_mmc(host->mmc->card) && mrq->sbc &&
+			if (mmc_card_mmc(mmc->card) && mrq->sbc &&
 			    !(mrq->sbc->arg & 0xFFFF0000))
 				rawcmd |= 0x2 << 28; /* AutoCMD23 */
 		}
@@ -1070,9 +1072,10 @@ static int msdc_auto_cmd_done(struct msdc_host *host, int events,
  */
 static void msdc_recheck_sdio_irq(struct msdc_host *host)
 {
+	struct mmc_host *mmc = mmc_from_priv(host);
 	u32 reg_int, reg_inten, reg_ps;
 
-	if (host->mmc->caps & MMC_CAP_SDIO_IRQ) {
+	if (mmc->caps & MMC_CAP_SDIO_IRQ) {
 		reg_inten = readl(host->base + MSDC_INTEN);
 		if (reg_inten & MSDC_INTEN_SDIOIRQ) {
 			reg_int = readl(host->base + MSDC_INT);
@@ -1080,7 +1083,7 @@ static void msdc_recheck_sdio_irq(struct msdc_host *host)
 			if (!(reg_int & MSDC_INT_SDIOIRQ ||
 			      reg_ps & MSDC_PS_DATA1)) {
 				__msdc_enable_sdio_irq(host, 0);
-				sdio_signal_irq(host->mmc);
+				sdio_signal_irq(mmc);
 			}
 		}
 	}
@@ -1113,7 +1116,7 @@ static void msdc_request_done(struct msdc_host *host, struct mmc_request *mrq)
 		msdc_unprepare_data(host, mrq);
 	if (host->error)
 		msdc_reset_hw(host);
-	mmc_request_done(host->mmc, mrq);
+	mmc_request_done(mmc_from_priv(host), mrq);
 	if (host->dev_comp->recheck_sdio_irq)
 		msdc_recheck_sdio_irq(host);
 }
@@ -1500,6 +1503,7 @@ static void msdc_enable_sdio_irq(struct mmc_host *mmc, int enb)
 
 static irqreturn_t msdc_cmdq_irq(struct msdc_host *host, u32 intsts)
 {
+	struct mmc_host *mmc = mmc_from_priv(host);
 	int cmd_err = 0, dat_err = 0;
 
 	if (intsts & MSDC_INT_RSPCRCERR) {
@@ -1523,12 +1527,13 @@ static irqreturn_t msdc_cmdq_irq(struct msdc_host *host, u32 intsts)
 			cmd_err, dat_err, intsts);
 	}
 
-	return cqhci_irq(host->mmc, 0, cmd_err, dat_err);
+	return cqhci_irq(mmc, 0, cmd_err, dat_err);
 }
 
 static irqreturn_t msdc_irq(int irq, void *dev_id)
 {
 	struct msdc_host *host = (struct msdc_host *) dev_id;
+	struct mmc_host *mmc = mmc_from_priv(host);
 
 	while (true) {
 		unsigned long flags;
@@ -1551,18 +1556,18 @@ static irqreturn_t msdc_irq(int irq, void *dev_id)
 		spin_unlock_irqrestore(&host->lock, flags);
 
 		if ((events & event_mask) & MSDC_INT_SDIOIRQ)
-			sdio_signal_irq(host->mmc);
+			sdio_signal_irq(mmc);
 
 		if ((events & event_mask) & MSDC_INT_CDSC) {
 			if (host->internal_cd)
-				mmc_detect_change(host->mmc, msecs_to_jiffies(20));
+				mmc_detect_change(mmc, msecs_to_jiffies(20));
 			events &= ~MSDC_INT_CDSC;
 		}
 
 		if (!(events & (event_mask & ~MSDC_INT_SDIOIRQ)))
 			break;
 
-		if ((host->mmc->caps2 & MMC_CAP2_CQE) &&
+		if ((mmc->caps2 & MMC_CAP2_CQE) &&
 		    (events & MSDC_INT_CMDQ)) {
 			msdc_cmdq_irq(host, events);
 			/* clear interrupts */
@@ -2456,7 +2461,6 @@ static int msdc_drv_probe(struct platform_device *pdev)
 
 	host->dev = &pdev->dev;
 	host->dev_comp = of_device_get_match_data(&pdev->dev);
-	host->mmc = mmc;
 	host->src_clk_freq = clk_get_rate(host->src_clk);
 	/* Set host parameters to mmc */
 	mmc->ops = &mt_msdc_ops;
@@ -2497,7 +2501,7 @@ static int msdc_drv_probe(struct platform_device *pdev)
 	mmc_dev(mmc)->dma_mask = &host->dma_mask;
 
 	if (mmc->caps2 & MMC_CAP2_CQE) {
-		host->cq_host = devm_kzalloc(host->mmc->parent,
+		host->cq_host = devm_kzalloc(mmc->parent,
 					     sizeof(*host->cq_host),
 					     GFP_KERNEL);
 		if (!host->cq_host) {
@@ -2582,7 +2586,7 @@ static int msdc_drv_remove(struct platform_device *pdev)
 	pm_runtime_get_sync(host->dev);
 
 	platform_set_drvdata(pdev, NULL);
-	mmc_remove_host(host->mmc);
+	mmc_remove_host(mmc);
 	msdc_deinit_hw(host);
 	msdc_gate_clock(host);
 
@@ -2594,7 +2598,7 @@ static int msdc_drv_remove(struct platform_device *pdev)
 	dma_free_coherent(&pdev->dev, MAX_BD_NUM * sizeof(struct mt_bdma_desc),
 			host->dma.bd, host->dma.bd_addr);
 
-	mmc_free_host(host->mmc);
+	mmc_free_host(mmc);
 
 	return 0;
 }
@@ -2629,6 +2633,7 @@ static void msdc_save_reg(struct msdc_host *host)
 
 static void msdc_restore_reg(struct msdc_host *host)
 {
+	struct mmc_host *mmc = mmc_from_priv(host);
 	u32 tune_reg = host->dev_comp->pad_tune_reg;
 
 	writel(host->save_para.msdc_cfg, host->base + MSDC_CFG);
@@ -2653,7 +2658,7 @@ static void msdc_restore_reg(struct msdc_host *host)
 		writel(host->save_para.pad_tune, host->base + tune_reg);
 	}
 
-	if (sdio_irq_claimed(host->mmc))
+	if (sdio_irq_claimed(mmc))
 		__msdc_enable_sdio_irq(host, 1);
 }