[PATCH linux-next v4 5/5] mtd: atmel-quadspi: add driver for Atmel QSPI controller
From: marex@denx.de (Marek Vasut)
Date: 2015-08-24 11:03:59
Also in:
linux-devicetree, linux-spi, lkml
On Monday, August 24, 2015 at 12:14:00 PM, Cyrille Pitchen wrote:
This driver add support to the new Atmel QSPI controller embedded into sama5d2x SoCs. It expects a NOR memory to be connected to the QSPI controller. Signed-off-by: Cyrille Pitchen <redacted> Acked-by: Nicolas Ferre <redacted>
Hi, [...]
+/* Register access macros */
These are functions, not macros :) btw is there any reason for these ? I'd say, just put the read*() and write*() functions directly into the code and be done with it, it is much less confusing. Also, why do you use the _relaxed() versions of the functions ?
+static inline u32 qspi_readl(struct atmel_qspi *aq, u32 reg)
+{
+ return readl_relaxed(aq->regs + reg);
+}
+
+static inline void qspi_writel(struct atmel_qspi *aq, u32 reg, u32 value)
+{
+ writel_relaxed(value, aq->regs + reg);
+}
+
+static inline u16 qspi_readw(struct atmel_qspi *aq, u32 reg)
+{
+ return readw_relaxed(aq->regs + reg);
+}
+
+static inline void qspi_writew(struct atmel_qspi *aq, u32 reg, u16 value)
+{
+ writew_relaxed(value, aq->regs + reg);
+}
+
+static inline u8 qspi_readb(struct atmel_qspi *aq, u32 reg)
+{
+ return readb_relaxed(aq->regs + reg);
+}
+
+static inline void qspi_writeb(struct atmel_qspi *aq, u32 reg, u8 value)
+{
+ writeb_relaxed(value, aq->regs + reg);
+}[...]
+static int atmel_qspi_run_command(struct atmel_qspi *aq,
+ const struct atmel_qspi_command *cmd)
+{
+ u32 iar, icr, ifr, sr;
+ int err = 0;
+
+ iar = 0;
+ icr = 0;
+ ifr = aq->ifr_width | cmd->ifr_tfrtyp;
+
+ /* Compute instruction parameters */
+ if (cmd->enable.bits.instruction) {
+ icr |= QSPI_ICR_INST(cmd->instruction);
+ ifr |= QSPI_IFR_INSTEN;
+ }
+
+ /* Compute address parameters */
+ switch (cmd->enable.bits.address) {
+ case 4:
+ ifr |= QSPI_IFR_ADDRL;
+ /*break;*/ /* fallback to the 24bit address case */What's this commented out bit of code for ? :-)
+ case 3: + iar = (cmd->enable.bits.data) ? 0 : cmd->address; + ifr |= QSPI_IFR_ADDREN; + break; + case 0: + break; + default: + return -EINVAL; + }
[...]
+no_data: + /* Poll INSTRuction End status */ + sr = qspi_readl(aq, QSPI_SR); + if (sr & QSPI_SR_INSTRE) + return err; + + /* Wait for INSTRuction End interrupt */ + init_completion(&aq->completion);
You should use reinit_completion() in the code. init_completion() should be used only in the probe() function and nowhere else.
+ aq->pending = 0; + qspi_writel(aq, QSPI_IER, QSPI_SR_INSTRE); + if (!wait_for_completion_timeout(&aq->completion, + msecs_to_jiffies(1000))) + err = -ETIMEDOUT; + qspi_writel(aq, QSPI_IDR, QSPI_SR_INSTRE); + + return err; +}
[...] Hope this helps :)