[PATCH 2/7] mtd: nand: Introduce nand_data_interface

On Tue, Sep 06, 2016 at 01:21:18PM +0200, Boris Brezillon wrote:

On Tue,  6 Sep 2016 12:39:10 +0200
Sascha Hauer [off-list ref] wrote:

quoted

Currently we have no data structure to fully describe a NAND timing.
We only have struct nand_sdr_timings for NAND timings in SDR mode,
but nothing for DDR mode and also no container to store both types
of timing.
This patch adds struct nand_data_interface which stores the timing
type and a union of different timings. This can be used to pass to
drivers in order to configure the timing.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---
 include/linux/mtd/nand.h | 109 ++++++++++++++++++++++++++---------------------
 1 file changed, 60 insertions(+), 49 deletions(-)

diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h
index 9af9575..19c73ef 100644
--- a/include/linux/mtd/nand.h
+++ b/include/linux/mtd/nand.h

@@ -568,6 +568,66 @@ struct nand_buffers {
 	uint8_t *databuf;
 };
 
+/*
+ * struct nand_sdr_timings - SDR NAND chip timings
+ *
+ * This struct defines the timing requirements of a SDR NAND chip.
+ * These information can be found in every NAND datasheets and the timings
+ * meaning are described in the ONFI specifications:
+ * www.onfi.org/~/media/ONFI/specs/onfi_3_1_spec.pdf (chapter 4.15 Timing
+ * Parameters)
+ *
+ * All these timings are expressed in picoseconds.
+ */
+
+struct nand_sdr_timings {
+	u32 tALH_min;
+	u32 tADL_min;
+	u32 tALS_min;
+	u32 tAR_min;
+	u32 tCEA_max;
+	u32 tCEH_min;
+	u32 tCH_min;
+	u32 tCHZ_max;
+	u32 tCLH_min;
+	u32 tCLR_min;
+	u32 tCLS_min;
+	u32 tCOH_min;
+	u32 tCS_min;
+	u32 tDH_min;
+	u32 tDS_min;
+	u32 tFEAT_max;
+	u32 tIR_min;
+	u32 tITC_max;
+	u32 tRC_min;
+	u32 tREA_max;
+	u32 tREH_min;
+	u32 tRHOH_min;
+	u32 tRHW_min;
+	u32 tRHZ_max;
+	u32 tRLOH_min;
+	u32 tRP_min;
+	u32 tRR_min;
+	u64 tRST_max;
+	u32 tWB_max;
+	u32 tWC_min;
+	u32 tWH_min;
+	u32 tWHR_min;
+	u32 tWP_min;
+	u32 tWW_min;
+};
+
+enum nand_data_interface_type {
+	NAND_SDR_IFACE,
+};
+

I know this is my code, and I'm the one to blame here, but can you
document the nand_data_interface fields (kerneldoc format)?

Sure, can do. Do you know what tCEH is? This one is not documented in
the ONFI spec.

Sascha

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